Keywords: Functionalized silicon, Self-assembled monolayers of organothiols, Sorption of iridium and rhodium, Online cyclotron-based experiments

In the field of superheavy elements, one of the first attempts to use gold-coated silicon was reported during the chemical characterization of element 112, Cn [1, 2]. Better chemical sorption of this element was observed on gold-modified surfaces rather than non-modified ones. In the case of element 113, Nh, an enhanced reactivity towards gold was observed, which prevented the proper chemical characterization of this element [3, 4]. Therefore, a need for new chemically modified gold-coated silicon detectors has emerged. The goal of such detectors is to selectively bind the atoms of interest but with weaker interactions. Element 109, meitnerium, which is expected to be a member of group 9 of the Periodic Table, has never been chemically characterized before. Therefore, this project aimed to study the adsorption of meitnerium's two closest homologs, namely iridium and rhodium, on functionalized surfaces.

In the first part of this project, the functionalization of gold-coated chips with 1-(11mercaptoundecyl)imidazole and 12-mercaptododecanoic acid SAMs, as well as the iridium(IV) and rhodium(III) sorption from hydrochloric acid solutions on the functionalized surfaces have been investigated. The functionalized surfaces were characterized off-line via several surface science techniques: atomic force microscopy, nanoprojectile secondary-ion mass spectrometry, Xray photoelectron spectroscopy, ellipsometry, and instrumental neutron activation analysis. The studied surfaces mimic functionalized gold-coated silicon detectors. The main goal of the devices of such kind is to compare the sorption properties of the superheavy element and its lighter homolog(s) during online сyclotron-based experiments.

In the second part of this project, the sorption of iridium, erbium (non-volatile elements), and astatine (a volatile element) on non-functionalized and thiolate-functionalized gold-coated iii silicon detectors have been studied during online сyclotron-based experiments. There is an interest in studying the sorption of iridium because it will help better the understanding of the chemistry of meitnerium in the future. By studying the sorption of iridium, erbium, and astatine, the comparison of the chemical behavior of the members of non-volatile and volatile elements, respectively, was performed. It was found that the detector position and material influence the sorption of these elements within the detector setup.

L'objectif principal des dispositifs de ce type est de comparer les propriétés de sorption de l'élément super-lourd et de son ou ses homologues plus légers lors d'expériences online au cyclotron.

Dans la deuxième partie de ce travail, la sorption de l'iridium et de l'erbium (éléments non volatils) ainsi que de l'astate (élément volatil) sur des détecteurs silicium recouverts d'or non fonctionnalisés et fonctionnalisés par des thionates a été étudiée au cours d'expériences online au cyclotron. Nous nous intéressons à l'étude de la sorption de l'iridium car elle permettra à l'avenir de mieux comprendre la chimie du meitnerium. Les résultats de l'étude de la sorption de l'iridium, de l'erbium et de l'astate nous ont permis de comparer le comportement chimique des membres des éléments non volatils et volatils, respectivement. Il a été constaté que la position et le matériau du détecteur influencent la sorption de ces éléments dans la configuration du détecteur.

RESUME

Dans le domaine de la synthèse des éléments super-lourds (Z = 104 et plus lourds) et les études expérimentales de leurs propriétés chimiques et physiques, l'une des premières tentatives d'utilisation de silicium recouvert d'une couche mince d'or a été annoncé lors de la caractérisation chimique de l'élément 112, le copernicium (symbole Cn) [1,2]. Une meilleure sorption chimique de cet élément a été observée sur les surfaces modifiées à l'or plutôt que sur les surfaces non modifiées. Dans le cas de l'élément 113, le nihonium (symbole Nh), une réactivité accrue vis-à-vis de l'or a été observée, ce qui a empêché la caractérisation chimique adéquate de ce nouvel élément [3,4]. Par conséquent, il faudrait développer de nouveaux détecteurs silicium recouverts d'or modifié chimiquement. Ces détecteurs ont pour le but de lier sélectivement les atomes d'intérêt mais avec des interactions plus faibles. L'élément 109, le meitnerium, qui devrait être un membre du groupe 9 du tableau périodique des éléments, n'a jamais été caractérisé chimiquement auparavant. Par conséquent, ce travail de thèse de doctorat vise à étudier l'adsorption de deux homologues les plus proches du meitnerium, l'iridium et le rhodium, sur des surfaces fonctionnalisées.

Dans la première partie de cette thèse, nous avons réalisé la fonctionnalisation de puces silicium recouvertes d'or avec des monocouches auto-assemblées de molécules organiques, 1-(11-mercaptoundecyl)imidazole ou d'acide 12-mercaptodecanoïque. Les surfaces fonctionnalisées ont été caractérisées par plusieurs techniques d'analyse de surface, notamment par microscopie à force atomique, spectrométrie de masse à ions secondaires par nanopjectiles, spectroscopie photoélectronique à rayons X, ellipsométrie et analyse instrumentale par activation neutronique. Puis la sorption d'iridium(IV) et de rhodium(III) à partir de solutions d'acide chlorhydrique sur les surfaces fonctionnalisées a été étudiée. Les surfaces étudiées donc imitent des détecteurs siliciums recouverts d'or fonctionnalisé.

INTRODUCTION 1.2

Monocouches auto-assemblées de molécules organiques Une approche bien connue de la fonctionnalisation de métaux, des oxydes métalliques et des semi-conducteurs est la formation de monocouches auto-assemblées (self-assembled monolayers en anglais, SAMs) à leur surface [5][6][7][8][9][10]. Les SAMs sont des arrangements de molécules qui peuvent être adsorbées spontanément sur des surfaces solides à partir d'une solution ou d'une phase gazeuse [6].

Les molécules de SAM sont composées de trois parties : un groupement de "tête" qui s'adsorbe en surface, une chaîne "séparatrices" (chaine aliphatique) et un groupement terminal fonctionnel [6]. Différents groupes de tête peuvent se lier à des métaux, oxydes métalliques et semi-conducteurs spécifiques [7][8][9][10].

Les SAM d'alcanethiolate sur les surfaces de métaux tels que or, argent, cuivre, palladium, platine, nickel constituent la classe de SAMs la plus largement étudiée et la plus connue [5][6][7][8][9][10].

Parmi tous les métaux cités, la préférence est donnée à l'or (Au), en particulier Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF]. Comme les métaux cubiques à faces centrées orientés [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] ont l'énergie libre de surface la plus faible, ces surfaces sont plus stables, contrairement aux surfaces métalliques orientées (100) qui subissent des reconstructions massives [11,12]. L'or est le métal le plus utilisé lors de l'adsorption de SAMs car il est facile à obtenir sous forme de couches minces, raisonnablement inerte, et forme des SAMs de bonne qualité [5,7].

Les thiols peuvent former de fortes liaisons covalentes thiolate-Au de 50 kcal/mol pendant la formation des SAMs [6], et ces SAMs peuvent être facilement préparés en phase liquide par l'immersion d'un substrat dans une solution éthanolique de thiol pendant 24 heures [6,7].

L'adsorption des thiols sur la surface de l'or se produit en deux étapes, commençant par la physisorption suivie de la chimisorption illustrée par l'équation 1 et l'équation 2, respectivement [6]. Au cours de cette dernière, une molécule de thiol, à savoir R-SH, est déprotonée et se transforme en un thiolate (RS-Au) [6].

Le processus d'adsorption peut être décrit comme suit : R-SH + Au (R-SH)physAu Eq. 1 (R-SH)physAu RS Au + 1/2H2 , Eq. 2 où R est un radical organique, dans le cas des alcanethiolates, R=CH3(CH2)n, où n est le nombre d'atomes de carbone présents dans une molécule [6].

Le schéma de l'auto-assemblage des alcanes thiolates est présenté dans la Figure 1 [6].

Il est important d'effectuer le dépôt de SAMs pendant 24 heures en raison de plusieurs étapes qui ont lieu pendant l'auto-assemblage. Comme il a été dit, la physisorption se produit d'abord, puis, au début de la chimisorption, les molécules sont principalement couchées. Au fil du temps, elles se redressent et finissent par former des molécules bien ordonnées dans une configuration dense [6].

Figure 1. Schéma de la formation de SAMs d'alcanethiolate sur Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] : physisorption (i), formation de la phase de dépôt (ii), nucléation de la phase de maintien (iii), achèvement de la phase de maintien (iv). Illustration utilisée avec la permission de la réf. [6] La grande affinité des thiols pour l'Au permet de créer des substrats organiques bien définis avec des fonctionnalités chimiques utiles et des propriétés qui peuvent être modifiées à l'avance en fonction de l'application [7].

L'alcanethiol à terminaison imidazole, 1-(11-mercaptoundecyl)imidazole (Im-C11-SH), étudié dans cette thèse a été choisi pour plusieurs raisons. L'objectif était de générer un substrat à base de SAMs alcanethiolate ayant des propriétés prédéfinies de fixation de Ir et Rh à partir de solutions d'acide chlorhydrique. Tout d'abord, il est bien connu que les liquides ioniques à base d'imidazolium ont déjà été utilisés dans l'extraction de Ir(IV) à partir de solutions d'acide chlorhydrique, atteignant des rapports de distribution élevés allant jusqu'à 71,4 [13]. Nous avons supposé que l'alcanethiol à terminaison imidazole serait également efficace pour la fixation de Ir(IV). D'autre part, le Rh(III) est extrait par les liquides ioniques à base d'imidazolium à un degré moindre, et les efficacités d'extraction ont été rapportées comme étant inférieures à 10% [14]. Néanmoins, l'idée était de comparer les efficacités de sorption de ces deux métaux en utilisant les SAMs Im-C11-SH. Deuxièmement, Im-C11-SH est un composé disponible dans le commerce qui simplifie la procédure de préparation des SAMs. Troisièmement, la revue de la littérature a montré que plusieurs tentatives réussies ont déjà été faites pour préparer des SAMs d'Im-C11-SH sur des surfaces d'or [15][16][17][18].

Le second thiol, l'acide 12-mercaptododécanoïque (MDDA), a été choisi pour comparer la sorption des métaux sur des SAMs avec différents groupes fonctionnels.

Objectif

Dans la première partie de ce travail de thèse, la fonctionnalisation de puces 1,690 ± 0,014 nm sur la surface de l'or. Après une semaine de stockage des échantillons, l'épaisseur est restée relativement la même, ce qui exclut les processus de dégradation pendant

Expérience online au cyclotron

Les résultats de l'expérience ont porté sur trois réactions de fusion-évaporation : 118 Sn( 40 Ar, 5n) 153 Er, 165 Ho( 40 Ar, 5n) 200 At, and 141 Pr( 40 Ar, 5n) 176 Ir en utilisant des détecteurs en silicium non fonctionnalisés et fonctionnalisés sont discutés dans ce chapitre. Les détails des réactions nucléaires réalisées ainsi que les détails techniques du dispositif expérimental sont abordés dans la section 2.3.3.

3.4.1 Détection de radionucléides sur des détecteurs en silicium non fonctionnalisés et fonctionnalisés.

L'effet de la position du détecteur dans la chambre de détection et du matériau du détecteur sur les taux de 152,153 Er, 199-201 At, and 173-176 Ir été étudié (Figure 4).

Conclusions

Des résultats prometteurs ont été obtenus lors de la production de 152,153 Er, 199-201 At, et 173-176 Ir qui ont démontré que le changement de position et de matériau du détecteur modifie la sorption du nucléide (Figure 6). Figure 6. Graphique 3D pour l'activité de 173-176 Ir en fonction de la position du détecteur et de matériaux de détecteur.

Le taux le plus élevé de 152,153 Er a été observé sur le détecteur en silicium recouvert d'or et sur les détecteurs en silicium nu. Le taux le plus élevé de 199,200,201 At a été observé sur le détecteur recouvert d'or, alors que les autres ont produit une efficacité égale. Pour 173-176 Ir, tous les matériaux ont produit une efficacité égale. L'étude du comportement chimique de 152,153 Er, 199-201 At et 173-176 Ir produits online a confirmé le caractère non volatil de Er et Ir et le caractère volatil d'At (Figure 7a). Elle a également révélé que les détecteurs en première position recueillaient la pluralité du produit. L'activité totale était constante quelle que soit la configuration (Figure 7b). Figure 7. Taux de comptage pour 173-176 Ir, 152,153 Er, et 199-201 At en fonction de: a) la position de détecteur; b) la configuration de détecteur.

La spectroscopie alpha a démontré que la fonctionnalisation de la surface du détecteur ainsi que son utilisation pendant les expériences online au cyclotron n'entraînent pas une dégradation de la résolution du détecteur, ce qui permet de les réutiliser. The latest release of the Periodic Table of chemical elements shown in Figure 1 contains 118 elements [5]. SHEs are the elements with the atomic number Z ≥ 104, they give an end to the actinide series and begin the series of transactinide elements [6]. The named elements exist due to shell stabilization of their nuclei which enables to keep the balance between the attractive nuclear force and the repulsive Coulomb force [6].

Figure 1. The Periodic Table of

Elements. Reprinted from ref. [5] SHEs are produced artificially through heavy-ion reactions during which two heavy nuclei fuse to form a compound nucleus (CN) [6]. Afterward, neutron evaporation leads to its deexcitation, and the formed nuclide alpha decays [6]. The excited heavy nucleus is very fissile due to a strong competition between spontaneous fission and alpha decay [6]. The survival probability of the CN is only 10 -2 -10 -3 per evaporation step [6]. Short half-lives (from seconds to microseconds) and small cross-sections (from nanobarns to femtobarns) of produced isotopes limit the chemical characterization of SHEs to 'single atoms' making so-called "one-atom-at-a-time" experiments especially challenging to perform [6,7].

There are two types of heavy-ion reaction mechanisms that are used to synthesize SHEs, namely "cold" and "hot" fusion. The schematics of the two reaction mechanisms are depicted in Figure 2. During cold fusion reactions, 208 Pb or 209 Bi targets are bombarded with appropriate heavy-ion projectiles of 54 Cr, 58 Fe, 62,64 Ni, or 68,70 Zn [6][7][8]. Typically, one or two neutrons are evaporated from the CN with the low excitation energy in the order of 10-15 MeV [7,8]. Formed nuclides alpha decay until spontaneous fission in the region of the known elements.

Elements 107 to 112 were synthesized through cold fusion reactions at Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany [6,7]. The last SHE that was synthesized using the cold fusion reaction was nihonium (Nh, Z=113) [9]. A 70 Zn ion beam bombarded a 209 Bi target producing 278 Nh isotope at the Institute of Physical and Chemical Research (RIKEN) in Wako City, Japan in 2004 [9]. Beam irradiations continued until 2012 which allowed for the production of a few atoms of nihonium [10]. The discovery of nihonium was recognized by the International Union of Pure and Applied Chemistry (IUPAC) in 2013 [11]. The cross-section of the 209 Bi( 70 Zn, n) 278 Nh reaction is only ~20 fb; such a small value indicated the inability to utilize the cold-fusion mechanism to synthesize elements with Z>113 [12]. During hot fusion reactions, an actinide target ( 238 U, 242,244 Pu, 243 Am, 248 Cm, 249 Bk, 249 Cf, or 254 Es) is bombarded with highly accelerated light-ion projectiles of 48 Ca, 26 Mg, 18 O, or 22 Ne [6][7][8]. Usually, three or five neutrons are evaporated from the CN with the excitation energy of 40-50

MeV [6,8]. The cross sections for the production of SHEs can be up to 100 times larger than those measured during cold fusion reactions [7]. Often, decay chains end in unknown regions which makes it challenging to identify nuclides.

Elements 114 to 118, flerovium to oganesson, with more neutron-rich nuclides, as well as multiple isotopes of elements 112, copernicium, and 113, nihonium, were produced through hot fusion reactions at Flerov Laboratory of Nuclear Reactions (FLNR), Joint Institute for Nuclear Research (JINR) in Dubna, Russia [6,7]. Element 118, oganesson, was first synthesized in 2002 during the experiment using a 48 Ca ion beam on a 249 Cf target to produce 294 Og, only one event of this isotope was detected [7,13]. The second experiment with the higher sensitivity resulted in the detection of two additional events of the isotope 294 Og [13]. The discovery of oganesson announced in 2005 [13] and its official recognition by IUPAC in 2016 [11] completed the seventh period of the periodic table [7].

Proper chemical studies must be performed to confirm whether a SHE belongs to a particular group it was placed in the Periodic Table [14]. The chemical properties of SHEs are strongly influenced by relativistic effects that increase with Z 2 and cause deviations in the periodicity of the chemical properties [8,[14][15][16][17]. The electrons of SHEs orbiting the highly charged nucleus closer to it are accelerated to relativistic velocities due to the stronger Coulomb forces that the electrons experience [7]. Consequently, the electron mass increases according to:

𝑚 = 𝑚 𝑜 [(1 -(𝜈/𝑐) 2 ] -1/2 , Eq. 1
where 𝑚 𝑜 is the rest mass of the electron, 𝜈 is the velocity of the electron, and 𝑐 is the speed of light [14,17].

The relativistic mass increase of the electron results in the contraction and stabilization of spherically symmetric s and p1/2 atomic orbitals (AOs) [14,17]. This is known as a direct relativistic effect that originates from the inner K-and L-shell regions [14,17]. The expansion and destabilization of the p3/2, d, f, g, etc. AOs, caused by the increased screening of the nucleus by the relativistically contracted s and p1/2 AOs, is known as the indirect (the second) relativistic effect [14,17]. The spin-orbit splitting of the AOs with the orbital quantum number l>1 is called the third relativistic effect [14,17]. For instance, the splitting of the three isoenergetic p levels and the electron distribution into the more stabilized p1/2 and the less stabilized p3/2 subshells [7]. The splitting of the isoenergetic d levels is induced as well [7].

Overall, relativistic effects cause big changes in the orbital geometry as well as stronger electron binding in atoms [7]. Their impact on the valence orbitals of the heavier elements is bigger compared to that for lighter homologs [14]. This might result in different chemical properties of SHEs and their lighter congeners [14]. Therefore, rapid chemical techniques must be developed to characterize the chemical properties of SHEs and verify their position in the Periodic Table .   1

.1.1 Meitnerium

Meitnerium (Mt, Z=109) is a SHE located in group 9 of the Periodic Table [8]. Mt was synthesized for the first time during an experiment at GSI in 1982 [18][START_REF] Moody | The Chemistry of Superheavy Elements[END_REF][START_REF] Hofmann | The Chemistry of Superheavy Elements[END_REF]. It was produced using the reaction 209 Bi( 58 Fe, n) 266 Mt performed at the new at that time Separator for Heavy Ion reaction Products (SHIP) [18]. The latest SHIP setup can be found in Figure 3. The observed one-event decay chain that consisted of two uninterrupted alpha disintegrations followed by fission was assigned to the isotope 266 Mt [18]. The cross-section of the reaction was estimated to be about 10 -35 cm 2 , and the excitation energy of the compound nucleus was estimated to be in the range of 20-26 MeV [18]. A more detailed description of the results was published in 1984 [START_REF] Münzenberg | Evidence for Element 109 from One Correlated Decay Sequence Following the Fusion of 58 Fe with 209 Bi[END_REF] that were finally confirmed in 1988 [START_REF] Münzenberg | New Results on Element 109[END_REF]. The combined result of the two experiments reported the half-life of (3.4 -1.3 +6.1 ) ms for 266 Mt and the cross-section of (10 -6 +10 ) pb for the reaction provided above [START_REF] Münzenberg | New Results on Element 109[END_REF]. Reprinted from ref. [START_REF]The SHIP Setup[END_REF].

12 decay chains of 266 Mt were measured using three different beam energies in an experiment conducted in 1997 [START_REF] Hofmann | Excitation Function for the Production of 265 108 and 266 109[END_REF]. The mean half-life of 266 Mt of (1.7 -0.4 +0.6 ) ms and the production cross-section of (7.5 ± 2.7) pb were obtained [START_REF] Hofmann | Excitation Function for the Production of 265 108 and 266 109[END_REF]. The wide range of 𝛼 energies from 10.5 to 11.7

MeV indicated the existence of complicated level and decay schemes for 266 Mt [START_REF] Hofmann | Excitation Function for the Production of 265 108 and 266 109[END_REF].

A different nuclear reaction 208 Pb( 59 Co, n) 266 Mt was studied using the Berkeley Gas-filled

Separator at the Lawrence Berkeley National Laboratory (LBNL) 88-Inch Cyclotron in 2009 [START_REF] Nelson | Comparison of Complementary Reactions in the Production of Mt[END_REF].

The half-life of 266 Mt of (3.3 -1.0 +2.5 ) ms and the cross-section of (7.7 -3.3 +5.5 ) pb were measured [START_REF] Nelson | Comparison of Complementary Reactions in the Production of Mt[END_REF] and reported to be consistent with the latest values reported by Hofmann et al. [START_REF] Hofmann | Excitation Function for the Production of 265 108 and 266 109[END_REF]. The CN excitation energy was 14.9 MeV [START_REF] Nelson | Comparison of Complementary Reactions in the Production of Mt[END_REF]. The decay properties of daughter nuclides were also consistent with the results published in the literature [START_REF] Nelson | Comparison of Complementary Reactions in the Production of Mt[END_REF].

The more neutron-rich isotope 268 Mt was detected in the 𝛼-decay chain of 272 Rg [START_REF] Hofmann | The New Element 111[END_REF][START_REF] Hofmann | New Results on Elements 111 and 112[END_REF].

The half-life of 268 Mt was measured to be (70 -30 +100 ) ms in an earlier work [START_REF] Hofmann | The New Element 111[END_REF] and (42 -12 +29 ) ms in a later work conducted by Hofmann et al. [START_REF] Hofmann | New Results on Elements 111 and 112[END_REF]. The mean 𝛼 energy for 268 Mt was 10.258 MeV taken as an average of 𝛼 energies from three decay chains of 272 Rg [START_REF] Hofmann | New Results on Elements 111 and 112[END_REF].

The isotope 270 Mt with the mean half-life of (0.69 -0.26 +0. 95 ) s was found in the decay chain of 278 Nh produced in the 209 Bi( 70 Zn, n) 278 Nh reaction [10]. The 𝛼-decay energies were 10.03±0.07 and 10.26±0.07 MeV [10]. All Mt isotopes that were discovered and identified during the coldand hot-fusion reactions are listed in Table 1. The chemical properties of Mt have not been characterized yet due to low cross-sections and short half-lives of Mt isotopes (less than one second) produced during cold-fusion reactions making chemical investigations hard to perform [8]. Thus far, only theoretical predictions were performed.

Mt is predicted to have 6d 7 7s 2 ground state, its properties are expected to be similar to those of its lighter homologs, iridium (Ir, Z=77) and rhodium (Rh, Z=45) [17]. However, strong relativistic effects are predicted to have a bigger impact on the chemical properties of Mt located in the seventh period of the Periodic Table rather than those of its lighter homologs in the sixth and fifth periods [17].

The ionization potential (IP) of 8.7 eV for Mt was calculated using the Dirac-Fock (DF) theory [START_REF] Fricke | Recent Impact of Physics on Inorganic Chemistry[END_REF]. It is lower than the IP value of 8.967 eV reported for Ir, whereas ideally, it should be larger [17]. It is necessary to perform more accurate calculations for Mt in the near future [17].

The most stable oxidation states for Mt are expected to be +1 (in the aqueous solution), +3, and +6 [START_REF] Fricke | Recent Impact of Physics on Inorganic Chemistry[END_REF]. The prediction of the stable +6 oxidation state means that volatile hexafluorides of Mt might be formed, making chemical separation experiments feasible to perform [START_REF] Fricke | Recent Impact of Physics on Inorganic Chemistry[END_REF]. Overall, the chemistry of Mt is predicted to show a strong tendency toward the formation of complex ions of this element [START_REF] Fricke | Recent Impact of Physics on Inorganic Chemistry[END_REF].

The bond length in MtH3, MtC -, MtN were calculated using the density functional method with the Amsterdam Density Functional (ADF) program package [START_REF] Pyykkö | Molecular Single-Bond Covalent Radii for Elements 1-118[END_REF][START_REF] Pyykkö | Triple-Bond Covalent Radii[END_REF]. The single-bond and the triple-bond radii of the 6d element, Mt, are about 8-9 pm larger than for its 5d analog, Ir, as can be seen in Table 2. It means that relativistic effects do not change the general periodic trend in group 9, and Mt still forms another normal d trend: 4d≤5d<6d. Nonetheless, longer-lived isotopes of Mt might be produced during hot-fusion reactions involving 48 Ca beams on actinide targets which will make chemical characterization possible [8].

Unfortunately, Mt has been produced only indirectly in hot-fusion reactions [START_REF] Moody | The Chemistry of Superheavy Elements[END_REF].

For example, 278 Mt with a half-life of (7.7 -3.5 +37 ) s is a decay product observed in the decay chain of 294 Ts produced in 249 Bk( 48 Ca,3n) 294 Ts reaction [START_REF] Oganessian | Eleven New Heaviest Isotopes of Elements Z = 105 to Z = 117 Identified among the Products of 249 Bk+ 48 Ca Reactions[END_REF].

276 Mt and 275 Mt with the half-lives of (0.68 -0.12 +0.20 ) s and (9.7 -4.4 +46 ) ms, respectively, were found to be members of the decay chains of the Mc isotopes produced during the 243 Am( 48 Ca,3n) 288 Mc and the 243 Am( 48 Ca,4n) 287 Mc reactions, respectively [START_REF] Oganessian | New Insights into the 243 Am + 48 Ca Reaction Products Previously Observed in the Experiments on Elements 113, 115, and 117[END_REF][START_REF] Oganessian | Synthesis of Elements 115 and 113 in the Reaction 243 Am + 48 Ca[END_REF].

The decay chain of 282 Nh produced during the 237 Np( 48 Ca,3n) 282 Nh reaction contains the Volatile oxides, hydroxides, or carbonyls of Mt might be proper species for the chemical separation and characterization of this element using gas-phase chromatography techniques [8,[START_REF] Iliaš | Carbonyl Compounds of Rh, Ir, and Mt: Electronic Structure, Bonding and Volatility[END_REF].

SHE Chemical Experiments

In the field of studying the chemical properties of SHE, the gas-solid chromatography method is the most effective way to perform one-atom-at-a-time experiments [4,8,14,17,[START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF].

Chemistry studies and the detection of single atoms of SHE occur in a chromatography column by registering their nuclear decay using silicon detectors or gold-coated silicon detectors [4].

Thermochromatography is a method in which a negative temperature gradient is applied to a chromatography column [8,[START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF]. Volatile species are transported through the column by a carrier gas [START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF]. The time the species are adsorbed on the surface of the column increases exponentially due to the applied negative temperature gradient [START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF]. Species with different volatility form distinct deposition peaks depending on their adsorption enthalpy (-∆𝐻 𝑎𝑑𝑠 ) on the surface of the column [START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF]. As a result, this allows the separation of different species [START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF].

-∆𝐻 𝑎𝑑𝑠 values can be calculated by knowing the event distribution in the column and using Monte Carlo simulations based on the adsorption model [14]. The deposition temperature (𝑇 𝑎 ) is the characteristic quantity that is associated with the deposition zones registered by a series of planar silicon detectors comprising a column [14,[START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF].

Typically, two detector arrays face each other in close proximity, therefore, the probability to observe a series of 𝛼-decays of a produced isotope is high [START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF]. The sensitivity of thermochromatography experiments for transactinides decaying by spontaneous fission is high due to the fact that all the species get adsorbed eventually on the column surface, and each nuclide's decay is registered [START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF]. Consequently, the position of each decay in the column can explain the chemistry of species under study [START_REF] Türler | Chemical Studies of Elements with Z⩾104 in Gas Phase[END_REF]. A temperature profile and an integral chromatogram resulting from thermochromatography are pictured in Figure 4. During the chemical characterization of copernicium (Cn, Z=112), silicon detectors coated with a layer of gold were used for the first time [1]. The 242 Pu( 48 Ca, 3n) 287 Fl reaction was performed at the U-400 cyclotron at the FLNR [1]. The thermochromatographic in situ volatilization combined with the cryo-online detector (COLD) was employed [1]. The experimental setup is shown in Figure 5. The detector array consisted of 32 pairs of ion-implanted planar silicon detectors that face each other and form a chromatographic channel [1]. The detector surface on one side of the channel was coated with 30-50 nm of gold [1]. Two negative temperature gradients of +24 to -184°C and +35 to -180°C were applied in this experiment [1].

The adsorption of two atoms of 283 Cn, produced after the 𝛼-decay of the short-lived 287 Fl, was observed on the gold-covered side of the detector [1]. Cn was found to be a very volatile element that showed a metallic interaction with the gold surface, confirming the belonging of Cn to group 12 of the Periodic Table [1].

A year later, the overall efficiency of the experiment was approximately 3 times higher, and three additional decay chains of 283 Cn were obtained [2]. The temperature gradient was held between +32 and -164°C [2]. Cn was confirmed to be more volatile than its lighter homologs. The adsorption enthalpy of Cn on the gold surface was determined to be -∆𝐻 𝑎𝑑𝑠 𝐴𝑢 (Cn) = 52 -3 +4 kJ/mol which was lower than that for its lighter homologs [2]. The calculated -∆𝐻 𝑎𝑑𝑠 𝐴𝑢 value was higher than the theoretically predicted adsorption enthalpy using a physisorption model [2].

The obtained results confirmed the formation of a metallic bond during the interaction between Cn and Au which was weaker than that for its lighter homologs [2]. This demonstrated that the trend of increasing stabilization of the elemental atomic state due to relativistic effects is saved in group 12 of the Periodic Table .   The results of the first Nh chemistry experiments performed at FLNR without preseparation showed that Nh strongly reacts with gold: -∆𝐻 𝑎𝑑𝑠 𝐴𝑢 >60 kJ/mol [3]. It was concluded that the observed species was either atomic Nh or its hydroxide NhOH [3]. However, improvements in the used technique needed to be made, such as using an electromagnetic recoil separator [4]. This would increase the probability of detection of Nh and its daughters while the background in 𝛼-decay spectra caused by volatile byproducts of a multi-nucleon transfer reaction would be decreased [4].

After the successful chemical characterization of flerovium (Fl, Z=114), at the gas-filled separator TransActinide Separator and Chemistry Apparatus (TASCA) at GSI using gold-coated silicon detectors [START_REF] Yakushev | Gas-Phase Chemistry of Element 114, Flerovium[END_REF], experiments aimed at the study of Nh chemistry using a similar setup were initiated [4]. Therefore, a pulsed 48 Ca 10+ beam bombarded a 243 Am target wheel to produce 288 Mc using the Universal Linear Accelerator (UNILAC) [4]. The ions of interest were thermalized in a He/Ar gas mixture inside the Recoil Transfer Chamber (RTC) and flushed out to the Cryo Online Multidetector for Physics And Chemistry of Transactinides (COMPACT) [4]. The schematic of the experimental setup is displayed in Figure 6. The first COMPACT array consisted of 16 pairs of silicon detectors followed by 16 pairs of gold-coated silicon detectors and was kept at room temperature [4]. The second COMPACT array consisted of 32 pairs of gold-coated silicon detectors, and a negative temperature gradient was applied to it [4].

Unfortunately, no decay chains of 288 Mc or its 𝛼-decay product, 284 Nh, were observed [4].

Only one spontaneous fission event was observed which could not be assigned to the decay of the named isotopes [4]. This suggested that Nh has higher reactivity than Cn and Fl given the fact that Nh has one unpaired electron in the outermost electron shell: 7s 2 7p1/2 1 [4].

Possibly, Nh was irreversibly adsorbed on the inner wall of the PTFE tube which connected the RTC to the first COMPACT which led to a loss of Nh atoms [4]. The non-observation of Nh might also be explained by the formation of NhOH which is predicted to be non-volatile [4]. As a result, an improved detector array called miniCOMPACT was developed [4]. Such a setup does not require any transportation tubes between the RTC and the detection system [4]. The transport efficiency from the RTC into the miniCOMPACT was approximately 30% for the highly reactive francium isotopes, 202-205 Fr [4]. This implies that studies of Nh and Mc chemistry are now possible [4].

Iridium and Rhodium Chemistry

Ir (Z=77) and Rh (Z=45) are expected to be homologs of Mt. Ir has two stable naturally occurring isotopes: 191 Ir and 193 Ir with abundancies of 37.3% and 62.7%, respectively. Rh has one naturally occurring isotope: 103 Rh. In the earth's crust, the concentration is 0.3-5 ng/g for Ir and less than 0.5 ng/g for Rh.

In a U.S. Geological Survey report, Ir and Rh are reported as critical minerals which means their supply is at risk [START_REF] Survey | Mineral Commodity Summaries 2022[END_REF]. The common minerals that contain Ir are alloys of osmium and iridium called osmiridium (syserkskite), iridosmium (nevyanskite), or ruthenosmiridium. Hollingworthite and irsarite contain both Ir and Rh. They are predominantly produced as by-products during the mining and refining of host commodities such as platinum and nickel [START_REF] Nassar | Methodology and Technical Input for the 2021 Review and Revision of the U.S. Critical Minerals List[END_REF].

To separate Ir and Rh from other platinum-group metals present in a commodity, they first need to be dissolved [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. After the dissolution step in hydrochloric acid (HCl) that can be used for this purpose with an oxidizing agent, the formed species can be separated and extracted employing liquid-liquid extraction [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. The recovery of Ir and Rh metals is achieved as a result [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. This is one of the reasons why significant attention is paid to the chemistry of Ir and Rh in HCl solutions.

The electron ground states of Ir and Rh are [Xe]4f 14 5d 7 6s 2 and [Kr]4d 8 5s 1 , respectively.

The most stable oxidation states of Ir are +3 and +4 [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. The most stable oxidation states of Rh are +1 and +3 [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. The oxidation states of Ir and Rh and corresponding examples of their compounds with different coordination numbers are listed in Table 3. Ir and Rh can form octahedral complexes with halide anions or ligands containing oxygen [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. HIr(CO)(PPh3)3

HRh(PF3)4 +2 Ir(CO)2Cl2 [Rh(C4N2S2)2] 2- [Ir(CO)2I3] - [Rh(OAc)2]2 +3 H3Ir(AsPh3)2 [IrCl6] 3- [Rh(H2O)6] 3+ +4 [IrCl6] 2- Cs2[RhCl6] +5 [IrF6] - [RhF5]4 +6 IrF6, RhF6
Ir and Rh have similar chemical behavior and exist in the form of different chlorocomplexes in HCl solutions depending on their pH [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. If the solution pH is below 2, Ir(IV)

predominantly exists in the form of IrCl5 -and IrCl6 2-complexes [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF][START_REF] Zakusilova | Extraction and Separation of Iridium(IV) and Rhodium(III) from Hydrochloric Acid Media by a Quaternary Ammonium-Based Hydrophobic Eutectic Solvent[END_REF][START_REF] Sun | Separation of Ir(IV) and Rh(III) from Mixed Chloride Solutions by Solvent Extraction[END_REF]. IrCl6 2-is reduced to IrCl6 3-in even more acidic HCl solutions [START_REF] Zakusilova | Extraction and Separation of Iridium(IV) and Rhodium(III) from Hydrochloric Acid Media by a Quaternary Ammonium-Based Hydrophobic Eutectic Solvent[END_REF][START_REF] Nguyen | Effect of HCl Concentration on the Oxidation of LIX 63 and the Subsequent Separation of Pd(II), Pt(IV), Ir(IV) and Rh(III) by Solvent Extraction[END_REF]. In the pH range from 2 to 7, IrCl4(OH)2 2-and IrCl2(OH)4 2-complexes are formed [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. In the pH range from 7 to 12, IrCl2(OH)4 2-and neutral IrO2•2H2O are predominant species [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. In an alkaline solution, the dark red-brown IrCl6 2- undergoes spontaneous reduction which leads to the formation of pale yellow-green IrCl6 3-. The speciation of Ir in HCl solutions is summarized in Table 4. Organic compounds containing phosphorus, arsenic and sulfur donors can reduce Ir(IV) to Ir(III) [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF].

Species IrCl6 2-IrCl4(OH)2 2- IrCl2(OH)4 2- IrCl2(OH)4 2- IrO2•2H2O IrCl6 3-
In an aqueous solution, Rh(III) exists in the form of a stable yellow hexaaqua ion Rh(H2O)6 3+ [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. When the pH of a solution is less than 1, hydroxy species Rh(H2O)5(OH) 2+ are formed [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. When Rh(H2O)6 3+ is heated in excess of HCl, rose-pink RhCl6 3-is formed [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. The major species of Rh(III) in HCl solutions are the following: RhCl(H2O)5 2+ , RhCl2(H2O)4 + , RhCl3(H2O)3, RhCl4(H2O)2 -, RhCl5(H2O) 2-and RhCl6 3- [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF][START_REF] Bernardis | A Review of Methods of Separation of the Platinum-Group Metals through Their Chloro-Complexes[END_REF][START_REF] Svecova | Rh(III) Aqueous Speciation with Chloride as a Driver for Its Extraction by Phosphonium Based Ionic Liquids[END_REF]. When Rh(H2O)6 3+ is heated in diluted HCl, cationic species of RhCl(H2O)5 2+ and RhCl2(H2O)4 + are formed [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. RhCl6 3+ becomes predominant with an increase in the HCl concentration [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. The speciation of Rh(III) in HCl solutions [START_REF] Benguerel | Speciation and Separation of Rhodium(III) from Chloride Solutions: A Critical Review[END_REF] is summarized in Figure 7.

Rh(III) speciation in HCl solution has been extensively studied, and all six stability constants of Rh(III) chloro-complexes are known [START_REF] Benguerel | Speciation and Separation of Rhodium(III) from Chloride Solutions: A Critical Review[END_REF]. However, only one cumulative stability constant of the Ir(IV) chloro-complex, IrCl6 2-, was estimated so far (β6=10 31 ) [START_REF] Lesch | Some Data on the Thermodynamics of Platinum Metal Compounds[END_REF].

Self-Assembled Monolayers (SAMs)

A well-known approach to the functionalization of metals, metal oxides, and semiconductors is the formation of self-assembled monolayers (SAMs) on top of them [START_REF] Vericat | Self-Assembled Monolayers of Thiolates on Metals: A Review Article on Sulfur-Metal Chemistry and Surface Structures[END_REF][START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF][START_REF] Love | Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology[END_REF][START_REF] Wilbur | Nanotechnology[END_REF][START_REF] Ulman | Formation and Structure of Self-Assembled Monolayers[END_REF][START_REF] Telegdi | Formation of Self-Assembled Anticorrosion Films on Different Metals[END_REF].

SAMs are arrangements of molecules that can be spontaneously adsorbed on solid surfaces from a solution or a vapor phase [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF].

SAMs molecules can be divided into three parts: a headgroup, a hydrocarbon chain, and a functional terminal group [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF]. Different headgroups can bind to specific metals, metal oxides, and semiconductors [START_REF] Love | Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology[END_REF][START_REF] Wilbur | Nanotechnology[END_REF][START_REF] Ulman | Formation and Structure of Self-Assembled Monolayers[END_REF][START_REF] Telegdi | Formation of Self-Assembled Anticorrosion Films on Different Metals[END_REF]. The literature review on different types of SAMs adsorbed on different substrates is summarized in Table 5.

Alkanethiolate SAMs on the surfaces of noble and coinage metals (gold, silver, copper, palladium, platinum, nickel) are the most broadly studied and popular class of SAMs [START_REF] Vericat | Self-Assembled Monolayers of Thiolates on Metals: A Review Article on Sulfur-Metal Chemistry and Surface Structures[END_REF][START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF][START_REF] Love | Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology[END_REF][START_REF] Wilbur | Nanotechnology[END_REF][START_REF] Ulman | Formation and Structure of Self-Assembled Monolayers[END_REF][START_REF] Telegdi | Formation of Self-Assembled Anticorrosion Films on Different Metals[END_REF].

Among all listed metals, the preference is made for gold (Au), in particular, Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF]. Due to the fact that face-centered cubic metals with [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] orientation have the lowest surface free energy, such surfaces are more stable unlike metal surfaces with (100) orientation which undergo massive reconstructions [START_REF] Somorjai | Introduction to Surface Chemistry and Catalysis[END_REF][START_REF] Kolasinski | Surface Science: Foundations of Catalysis and Nanoscience[END_REF]. Gold is the most widely used metal during SAMs adsorption because it is easy to obtain in a form of thin films, reasonably inert, and forms SAMs of good quality [START_REF] Vericat | Self-Assembled Monolayers of Thiolates on Metals: A Review Article on Sulfur-Metal Chemistry and Surface Structures[END_REF][START_REF] Love | Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology[END_REF].

Thiols can form strong thiolate-Au covalent bonds of 50 kcal/mol during the SAMs formation [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF], and these SAMs can be easily prepared in the liquid phase by the immersion of a substrate into an ethanolic thiol solution for up to 24 h [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF][START_REF] Love | Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology[END_REF].

Table 5. Different types of SAMs adsorbed on different substrates.

Substrate Type of SAMs Reference

Gold Alkanethiolate [START_REF] Qi | Binary Thiolate DNA/Ferrocenyl Self-Assembled Monolayers on Gold: A Versatile Platform for Probing Biosensing Interfaces[END_REF][START_REF] Ito | Nanoporous Thin Films Formed from Photocleavable Diblock Copolymers on Gold Substrates Modified 123 with Thiolate Self-Assembled Monolayers[END_REF][START_REF] Brown | Influence of Structural Dynamics on the Kinetics of Atomic Hydrogen Reactivity with Low-Temperature Alkanethiolate Self-Assembled Monolayers[END_REF][START_REF] Asyuda | Thermal Stability of Alkanethiolate and Aromatic Thiolate Self-Assembled Monolayers on Au(111): An X-ray Photoelectron Spectroscopy Study[END_REF][START_REF] Urcuyo | Aromatic and Aliphatic Thiol Self-Assembled Monolayers on Au: Anchoring and Delivering Copper Species[END_REF] Selenolate [START_REF] Protsailo | Electrochemical Characterization of the Alkaneselenol-Based SAMs on Au(111) Single Crystal Electrode[END_REF][START_REF] Ossowski | Thiolate Versus Selenolate: Structure, Stability, and Charge Transfer Properties[END_REF][START_REF] Ossowski | Relative Stability of Thiolate and Selenolate SAMs on Ag(111) Substrate Studied by Static SIMS. Oscillation in Stability of Consecutive Chemical Bonds[END_REF] Organogermane [START_REF] Owens | Octylgermane on Gold: Synthesis, Oxidation, and Pattern Formation[END_REF] Dodecyl sulfate [START_REF] Song | Sodium Dodecyl Sulfate Adsorption onto Positively Charged Surfaces: Monolayer Formation with Opposing Headgroup Orientations[END_REF] Silver Alkanethiolate [START_REF] Wang | Empirical Evidence for Roughness-Dependent Limit in Observation of Odd-Even Effect in Wetting Properties of Polar Liquids on n-Alkanethiolate Self-Assembled Monolayers[END_REF] Selenolate [START_REF] Ossowski | Relative Stability of Thiolate and Selenolate SAMs on Ag(111) Substrate Studied by Static SIMS. Oscillation in Stability of Consecutive Chemical Bonds[END_REF][START_REF] Han | Self-Assembled Monolayers of Aromatic Thiol and Selenol on Silver: Comparative Study of Adsorptivity and Stability[END_REF] Copper Alkanethiolate [START_REF] Rechmann | Carbon-Sulfur Bond Cleavage During Adsorption of Octadecane Thiol to Copper in Ethanol[END_REF] Amino acid [START_REF] Zhang | pH and Iodide Ion Effect on Corrosion Inhibition of Histidine Self-Assembled Monolayer on Copper[END_REF] Tetrazole [START_REF] Qiang | Self-Assembling Anchored Film Basing on Two Tetrazole Derivatives for Application to Protect Copper in Sulfuric Acid Environment[END_REF] Palladium Alkanethiolate [START_REF] Kumar | Catalyst Site Selection Via Control over Noncovalent Interactions in Self-Assembled Monolayers[END_REF] Platinum [START_REF] Solodenko | Atom Probe Study of 1-Octadecanethiol Self-Assembled Monolayers on Platinum (111) and (200) Surfaces[END_REF] Nickel [START_REF] Senthil Kumar | Fabrication of Ultra-Smooth and Oxide-Free Molecule-Ferromagnetic Metal Interfaces for Applications in Molecular Electronics under Ordinary Laboratory Conditions[END_REF] Titanium Organophosphonic acid, organophosphate, and organosilane [START_REF] Mani | Stability of Self-Assembled Monolayers on Titanium and Gold[END_REF] Iron Alkylamine [START_REF] Feng | Investigation of Alkylamine Self-Assembled Films on Iron Electrodes by SEM, FT-IR, EIS and Molecular Simulations[END_REF] Titanium oxide and silicon oxide Chlorosilane, alkoxysilane, carboxylic acid, and isocyanate [START_REF] Paz | Self-Assembled Monolayers and Titanium Dioxide: From Surface Patterning to Potential Applications[END_REF] Various alloy and metal oxides Hydroxamic, organophosphonic, carboxylic, and sulfonic acids [START_REF] Raman | Understanding Organic Film Behavior on Alloy and Metal Oxides[END_REF] Sapphire Carboxylic acid [START_REF] Taylor | Octadecanoic Acid Self-Assembled Monolayer Growth at Sapphire Surfaces[END_REF] Calcium fluoride Dodecyl sulfate [START_REF] Song | Sodium Dodecyl Sulfate Adsorption onto Positively Charged Surfaces: Monolayer Formation with Opposing Headgroup Orientations[END_REF] The adsorption of thiols on the gold surface occurs in two steps, beginning with physisorption followed by chemisorption as illustrated in Eq. 2 and Eq. 3, respectively [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF]. During the latter one, a thiol molecule, namely R-SH becomes deprotonated, turning into a thiolate (RS-Au) [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF].

The adsorption process can be described as follows:

R-SH + Au → (R-SH)physAu Eq. 2 (R-SH)physAu → RS-Au + 1/2H2 , Eq. 3
where R is an organic radical; in the case of alkanethiolates, R=CH3(CH2)n, where n is the number of carbon atoms present in a molecule [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF].

The scheme of the self-assembly of alkanethiolates is depicted in Figure 8 [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF]. It is important to perform the SAMs deposition for up to 24 h due to several steps taking place during the self-assembly. As it was said, the physisorption occurs first, then, at the beginning of the chemisorption, molecules are mostly laying down. In time, they turn into the standing-up phase finishing with the formation of desired well-ordered molecules in a close-packed configuration [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF]. [START_REF] Chen | Development of a Label-Free Impedance Biosensor for Detection of Antibody-Antigen Interactions Based on a Novel Conductive Linker[END_REF]. MDDA SAMs on gold substrates have recently been used to prepare DNA-modified liquidcrystal droplets which can be potentially applied in surface information visualization and detection kits [START_REF] Yang | DNA-Modified Liquid Crystal Droplets[END_REF].

The literature review showed that thiolate SAMs on Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] have been utilized to study the interaction between various metals and terminal functional groups of SAMs [START_REF] Urcuyo | Aromatic and Aliphatic Thiol Self-Assembled Monolayers on Au: Anchoring and Delivering Copper Species[END_REF][START_REF] Zaitouna | Design and Characterization of a Metal Ion-Imidazole Self-Assembled Monolayer for Reversible Immobilization of Histidine-Tagged Peptides[END_REF][START_REF] Magallanes | Interaction of Aqueous Cu(II) with Carboxylic Acid and Alcohol Terminated Self Assembled Monolayers: Surface and Interfacial Characterization[END_REF][START_REF] Ivanova | Palladium and Platinum Deposition onto 4-Mercaptopyridine SAMs[END_REF].

Magallanes et al. characterized the interaction between copper(II) ions and carboxylic acid-or

alcohol-terminated thiolate SAMs on Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] for the future preparation of heavy metal ion sensors [START_REF] Magallanes | Interaction of Aqueous Cu(II) with Carboxylic Acid and Alcohol Terminated Self Assembled Monolayers: Surface and Interfacial Characterization[END_REF]. In their work, 3-mercaptopropionic and 16-mercaptohexadecanoic acids were investigated [START_REF] Magallanes | Interaction of Aqueous Cu(II) with Carboxylic Acid and Alcohol Terminated Self Assembled Monolayers: Surface and Interfacial Characterization[END_REF]. A new capacitor sensor was developed for the chromium(VI) determination by Kochana et.

al [START_REF] Kochana | Study on Self-Assembled Monolayer of Functionalized Thiol on Gold Electrode Forming Capacitive Sensor for Chromium(VI) Determination[END_REF], in their work, an Au(111) electrode was functionalized with ethanethiolate SAMs with the functional group exhibiting affinity for chromium(VI) anions. Ivanova et al. [START_REF] Ivanova | Palladium and Platinum Deposition onto 4-Mercaptopyridine SAMs[END_REF] reported the electrochemical deposition of monoatomic high layers of palladium and platinum on 4-mercaptopyridine SAMs on Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] electrodes. In the work of Zaitouna and Lai [START_REF] Zaitouna | Design and Characterization of a Metal Ion-Imidazole Self-Assembled Monolayer for Reversible Immobilization of Histidine-Tagged Peptides[END_REF], gold disk electrodes were modified with mixed SAMs containing Im-C11-SH. They were used to coordinate divalent metals such as zinc(II), cobalt(II), and nickel(II) through the surface-immobilized imidazole terminal groups for the subsequent reversible immobilization of histidine-tagged peptides [START_REF] Zaitouna | Design and Characterization of a Metal Ion-Imidazole Self-Assembled Monolayer for Reversible Immobilization of Histidine-Tagged Peptides[END_REF].

However, there were no works reported on the application of the Au(111) surfaces functionalized with Im-C11-SH SAMs or MDDA for the sorption of Ir and Rh from liquid or gas phases.

The imidazole-terminated alkanethiol, Im-C11-SH, studied in this dissertation was chosen for several reasons. The goal was to generate an alkanethiolate SAMs-based substrate with predefined properties of binding Ir and Rh from hydrochloric acid solutions. First of all, it is wellknown that imidazolium-based ionic liquids have already been used in the Ir(IV) extraction from hydrochloric acid solutions reaching high distribution ratios of up to 71.4 [START_REF] Papaiconomou | Extraction of Iridium(IV) from Aqueous Solutions Using Hydrophilic/Hydrophobic Ionic Liquids[END_REF]. The assumption was made that the imidazole-terminated alkanethiol would be effective in the binding of Ir(IV) as well. On the other hand, Rh(III) is extracted by imidazolium-based ionic liquids to a lower degree, and the extraction efficiencies were reported to be less than 10% [START_REF] Yan | Separation of Pt(IV), Pd(II), Ru(III), and Rh(III) from Chloride Medium Using Liquid-Liquid Extraction with Mixed Imidazolium-Based Ionic Liquids[END_REF]. Nevertheless, the idea was to compare the surface saturation of Im-C11-SH SAMs with these two metals. Secondly, Im-C11-SH is a commercially available compound that simplifies the procedure of SAMs preparation.

The second thiol, MDDA, was chosen to compare the metal sorption on SAMs with different functional groups.

Scope

In the first part of this project, the functionalization of gold-coated chips with Im-C11-SH and MDDA SAMs, as well as Ir(IV) and Rh(III) sorption from hydrochloric acid solutions on Im-C11-SH SAMs were studied. The results of this study were important for designing new functionalized gold-coated silicon detectors.

In the second part of this project, the named detectors were used during online cyclotronbased experiments aimed at studying the sorption of iridium, erbium, and astatine on nonfunctionalized and functionalized silicon detectors.

The results of this study can possibly be used to develop a chemical system suitable for the chemical characterization of Mt in the future.

CHAPTER II EXPERIMENTS

Chemicals

Silicon wafers of 10 mm square in size and 525 m thick were coated with a 100 nm Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] film that had been primed with titanium (5 nm) to promote adhesion between silicon oxide and gold;

glass chips of aluminosilicate 10 mm square in size and 700 m thick were coated with a 50 nm Au [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF] film that had been primed with titanium (2.5 nm) (Platypus Technologies, LLC, USA).

Instruments and Analytical Techniques

Surface characterization techniques used for the measurement of the roughness, the surface coverage, the chemical state of SAMs, the kinetics of the SAMs degradation, the thickness of SAMs, and the surface saturation with Ir(IV) are described next.

Atomic Force Microscopy

The roughness measurements were acquired using a Bruker Dimension Icon AFM. All AFM images were obtained in scanning mode at room temperature using a rectangular Si3N4coated cantilever. Before AFM analysis, a stream of dry N2 was used to blow the dust particles off the analyzed surface. AFM images were analyzed in NanoScope Analysis© software.

Nanoprojectile Secondary-Ion Mass Spectrometry

A custom-built cluster-SIMS instrument, consisting of a liquid metal ion source of 520 keV Au400 4+ clusters, was employed to verify the presence of Im-C11-SH SAMs on the gold surface, and measure the coverage with SAMs. During the experiments, the ions impacted the front side of the bulk target at an angle of incidence of 45° from normal. The secondary ions were emitted/detected in the reflection direction. The NP-SIMS instrument is equipped with a reflectron-type time-of-flight (ToF) mass spectrometer, and an electron emission microscope, EEM [START_REF] Verkhoturov | Single Impacts of C60 on Solids: Emission of Electrons, Ions and Prospects for Surface Mapping[END_REF][START_REF] Eller | SIMS Instrumentation and Methodology for Mapping of Co-Localized Molecules[END_REF][START_REF] Eller | Testing Molecular Homogeneity at the Nanoscale with Massive Cluster Secondary Ion Mass Spectrometry[END_REF][94][95]. The EEM was used to detect secondary electrons for the ToF start signal. The secondary electrons, being detected as a magnified electron image, were used for the "electron collimator" of the bombarded area.

The data were acquired at the level of individual 520 keV Au400 4+ impacts with a repetition rate of 1000 impacts/s. This event-by-event bombardment-detection mode [START_REF] Verkhoturov | Single Impacts of keV Fullerene Ions on Free Standing Graphene: Emission of Ions and Electrons from Confined Volume[END_REF] allowed for the selection of specific impacts, in the present case those involving Im-C11-SH SAMs at the exclusion of signals from the uncoated gold support.

Secondary ions emitted/detected via a single projectile impact were collected as an individual mass spectrum. The number of individual mass spectra is ~106. They were collected from an area of 500 µm in diameter. The sum of all mass spectra (total mass spectrum) corresponds to the regular mass spectrum measured in the case of regular analysis by commercial NP-SIMS.

The peak intensity was normalized to the total number of events during an experiment. All spectra were collected in negative mode meaning the negative bias was applied to a sample, therefore, negatively charged secondary ions were emitted/detected. The same setup was used to detect Ir and Rh clusters bound to Im-C11-SH SAMs and measure SAMs coverage with the identified clusters.

X-ray Photoelectron Spectroscopy

An Omicron XPS/UPS system with Argus detector and Mg X-ray source, set to 250 W, was used to acquire X-ray photoelectron spectra. The analyzer pass energy was set to 40 eV.

Spectra were calibrated by setting the center of the strong Au 4f7/2 peak to 84.01 eV. XPS spectra were analyzed and fitted using the Marquardt method via CasaXPS© Software [START_REF] Fairley | Introduction to XPS and AES[END_REF][START_REF] Fairley | CasaXPS Processing Software for XPS Spectra[END_REF]. To fit sulfur XPS spectra containing two S 2p spin-orbit split components (S 2p3/2 and S 2p1/2) the branching ratio and the energy difference were set to 2:1 and 1.2 eV, respectively [START_REF] Kato | Strong Hydrogen Bonds at the Interface between Proton-Donating and -Accepting Self-Assembled Monolayers on Au(111)[END_REF][START_REF] Willey | Rapid Degradation of Alkanethiol-Based Self-Assembled Monolayers on Gold in Ambient Laboratory Conditions[END_REF].

Ellipsometry

An ellipsometer Alpha-SE from J.A. Woollam Co. was employed for ellipsometric measurements. An angle of incidence was set to 70°, and all measurements were acquired in a standard mode with the data acquisition rate of 10 sec. CompleteEASE® software was used to measure the SAMs thickness. A refractive index (n) of 1.450 for SAMs was used [START_REF] Prato | Optical Characterization of Thiolate Self-Assembled Monolayers on Au(111)[END_REF][START_REF] Bain | Formation of Monolayer Films by the Spontaneous Assembly of Organic Thiols from Solution onto Gold[END_REF] which is a default Cauchy parameter. The Cauchy layer was used to fit the data and determine the thickness of SAMs.

Instrumental Neutron Activation Analysis (INAA)

This technique was utilized to measure the concentration of Ir(IV) and Rh(III) in the aqueous phase before and after sorption on non-functionalized and functionalized precleaned goldcoated substrates. The comparator method of INAA -in which calibrators and the experimental samples are irradiated, and gamma-ray emissions are counted under identical conditions -was employed [START_REF] Greenberg | Neutron Activation Analysis: A Primary Method of Measurement[END_REF].

Aliquots and Rh(III) measurements are presented in Table 6. The procedure of precleaning the surface of gold-coated silicon samples, and their regeneration after SAMs deposition was designed based on a surface regeneration technique developed by Johnson and Mutharasan [START_REF] Johnson | Regeneration of Gold Surfaces Covered by Adsorbed Thiols and Proteins Using Liquid-Phase Hydrogen Peroxide-Mediated UV-Photooxidation[END_REF], in particular liquid-based hydrogen peroxide (H2O2)mediated UV-photooxidation (liquid-UVPO) treatment. Such a technique could replace a more aggressive and destructive method of Im-C11-SH SAMs removal, involving a "piranha" solution [START_REF] Wei | Direct Wiring of Cytochrome C's Heme Unit to an Electrode: Electrochemical Studies[END_REF].

A sample was placed into a Petri dish, and 170 μL of a 30% H2O2 solution was added to cover the whole surface area of the chip. The Petri dish was placed into the UV sterilizer, and the UV light was turned on for 30 min. After 30 min, the drop of H2O2 was refreshed to provide a high concentration of hydroxyl radicals. The Petri dish was placed back into the UV-sterilizer for 30 more min. Afterward, the chip was washed with a copious amount of a deoxygenated ethanol solution using a glass Pasteur pipette (around 10 times). The same procedure was used to remove thiolate SAMs from the surface during all experiments, except for XPS measurements where the sample was treated twice in a row. To prepare the deoxygenated ethanol solution, ethanol was briefly heated in a water bath of a rotary evaporator (T = 55°C, t = 15 min). The optimal rotation speed was 250 rpm. The procedure of SAMs deposition was designed based on the works of Yamamoto et al.

[106], Kato et al. [START_REF] Kato | Strong Hydrogen Bonds at the Interface between Proton-Donating and -Accepting Self-Assembled Monolayers on Au(111)[END_REF], and Wei et al. [START_REF] Wei | Direct Wiring of Cytochrome C's Heme Unit to an Electrode: Electrochemical Studies[END_REF]. The precleaned chip was placed into the bottom of a 50 mL plastic tube using tweezers with plastic tips. To fully cover the chip, 3 mL of the prepared 1.6 mM or 5 mM ethanolic Im-C11-SH or MDDA solution was added. The plastic tube was wrapped with aluminum foil to avoid exposure to light. The cap of the tube was wrapped with Parafilm. The chip was submerged in the thiol solution for 21 h to ensure the formation of wellordered, standing-up thiolate molecules in a closed-packed configuration, and the highest coverage [START_REF] Vericat | Self-Assembled Monolayers of Thiolates on Metals: A Review Article on Sulfur-Metal Chemistry and Surface Structures[END_REF][START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF]. The immersion procedure was performed in the fume hood at ambient temperature.

amino imino 32
The next day, the chip was taken out of the solution using tweezers with plastic tips. It was washed with a copious amount of the deoxygenated ethanol solution using a glass Pasteur pipette (approximately 10 times).

To dry the chip, a rubber bulb with a plastic tip was used to blow the residual drops off the surface. Then, a stream of compressed Ar gas was used to completely dry the surface.

The schematic structures of Im-C11-SH and MDDA SAMs deposited on gold-coated silicon and glass chips are represented in Figure 10. Prior to the NP-SIMS analysis, the chips were washed with a copious amount of 0.55 M HCl solution using a glass Pasteur pipette (approximately 10 times). To dry the chips, a stream of compressed Ar gas was used.

Online Cyclotron-Based Experiments

The experiments described in this dissertation were performed at the Cyclotron Institute, Texas A&M University in two temporally separated experiments. The Cyclotron Institute has a normal conducting K150 and a superconducting K500 cyclotron. A schematic of the facility is illustrated in Figure 11.

Reactions of interest

Initially, the reaction 141 Pr( 40 Ar, 5n) 176 Ir was chosen to study the sorption of 176 Ir on chemically modified and non-modified silicon detectors. During the first experiment, the beam energy was 6.3 MeV/u (252 MeV), and the count rate of 176 Ir was low due to several reasons.

Firstly, the 141 Pr( 40 Ar, 5n) 176 Ir reaction has the low cross-section of 1-10 mb [START_REF] Kusawake | Angular-Momentum Effect in the Fusion Reaction of 141 Pr with 40 Ar Projectiles[END_REF], and 176 Ir has a low alpha branching ratio of 2.6% [START_REF] Singh | Nuclear Data Sheets for A = 172[END_REF]. The half-life of 176 Ir is 8.6 ± 0.4 s [START_REF] Singh | Nuclear Data Sheets for A = 172[END_REF]. Secondly, the quadrupole magnet of the AGGIE separator did not have enough field to properly focus the product into the simple Recoil Transfer Chamber, so the efficiency of the separator was too low. As a result, we switched to the reaction 118 Sn( 40 Ar, 5n) 153 Er which has the higher cross-section of ~50 mb [START_REF] Gauvin | Nuclear Reactions of 118 Sn, 121 Sb, and 127 I with Argon Ions[END_REF]. 153 Er has an alpha branching ratio of 53% and the half-life of 37.1 ± 0.2 s [START_REF] Singh | Nuclear Data Sheets for A=149[END_REF]. The first experiment was a proof of principle and is not discussed in this dissertation. After a few 200 At reaction has the cross-section of ~10 mb [START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF]. 200 At has the alpha branching ratio of 57% and the half-life of 43 ± 1 s [START_REF] Xiaolong | Nuclear Data Sheets for A = 196[END_REF]. Alpha-decay information for the named nuclides is summarized in Table 7. The results of the second experiment are discussed in detail in Section 3.4 of this dissertation. where T 1/2 is the half-life of a nuclide, I is the 𝛼-branching ratio, 𝜎 is the cross-section of a corresponding nuclear reaction.

Target Chamber

The target chamber illustrated in Figure 17 has three ladders attached to telescoping arms that are controlled remotely. The ladders and telescoping arms are shown in Figure 13 and Figure 14, respectively. At first, the beam goes through the degrader ladder with mounted aluminum degraders of various thicknesses (1.2-6.29 μm), including a blank. They are used to decrease the beam's energy and build the excitation function. This enables the selection of an appropriate degrader for a particular nuclear reaction at which the count rate of a produced nuclide is the highest. The next ladder the beam goes through is the target ladder which has a variety of targets mounted on it as shown in Figure 13. Remote access to the target ladder allows putting in place a specific target needed for a particular nuclear reaction. The target position is aligned with the beam trajectory so that the beam hits the center of the selected target.

For the 118 [START_REF] Parker | Molecular Plating: A Method for the Electrolytic Formation of Thin Inorganic Films[END_REF][START_REF] Parker | Molecular Plating II a Rapid and Quantitative Method for the Electrodeposition of the Rare-Earth Elements[END_REF][START_REF] Aumann | Preparation of Targets of Ca, Ba, Fe, La, Pb, Tl, Bi, Th and U by Electrodeposition from Organic Solutions[END_REF][START_REF] Mayorov | Heavy-Ion Beam Induced Effects in Enriched Gadolinium Target Films Prepared by Molecular Plating[END_REF]. A schematic of the electrodeposition cell is shown in Figure 15. A Faraday cup illustrated in Figure 13 is attached to the third ladder and allows to measure the primary beam intensity when it is put in place. During a nuclear reaction, the Faraday cup is set to a position that is out of the beam's trajectory.

Lastly, the target chamber has two silicon detectors, called Rutherford East and West, located ±30° from the beam axis and used to detect deflected beam nuclei. The ion source and the cyclotron performance can cause fluctuations in the beam intensity during the experiment.

Additionally, the areal density of the target might decrease in time due to the target sputtering created by the intense beam. These changes can be accounted for by normalizing the total number of events of a produced nuclide to the mean of Rutherford scattering events collected on the Rutherford East and West detectors. Also, the Rutherford detectors can be used to control the alignment between the beam and the target.

Finally, after hitting the target, the desired reaction products and the unreacted beam particles enter the AGGIE gas-filled separator.

AGGIE gas-filled separator

The separator was originally designed at Lawrence Berkley National Laboratory and named SASSY II [START_REF] Ghiorso | Recoil Spectrometer for the Detection of Single Atoms[END_REF] which was an improved version of the previous separator named SASSY [START_REF] Ghiorso | Sassy, a Gas-Filled Magnetic Separator for the Study of Fusion Reaction Products[END_REF]. It was later transferred to the Wright Nuclear Structure Laboratory of Yale University and named SASSYER [START_REF] Ressler | SASSYER: An Old Instrument for New Physics at Yale[END_REF]. Eventually, it was transferred to the Cyclotron Institute, Texas A&M University, and named AGGIE. Characterization of the AGGIE separator using beam has begun in 2019 and is currently in progress [START_REF] Folden | Characterization of the Aggie Gas-Filled Separator[END_REF].

AGGIE consists of two vertically focusing dipole magnets and one horizontally focusing quadrupole magnet placed between them in the configuration DvQhDv [START_REF] Ressler | SASSYER: An Old Instrument for New Physics at Yale[END_REF][START_REF] Folden | Characterization of the Aggie Gas-Filled Separator[END_REF]. The effective length of the three magnets is approximately 2.5 m [START_REF] Folden | Characterization of the Aggie Gas-Filled Separator[END_REF]. A picture of AGGIE is illustrated in The purpose of AGGIE is to separate the produced ions of interest from the primary beam [START_REF] Ressler | SASSYER: An Old Instrument for New Physics at Yale[END_REF]. The separation is done based on their magnetic rigidity, 𝐵𝜌, defined as the momentum of an ion, 𝑚𝜈, divided by its charge state, 𝑞:

𝐵𝜌 = 𝛾𝑚𝜈 𝑞 , Eq. 4
where 𝐵 is the strength of a magnetic field, 𝜌 is the radius of curvature of motion, 𝛾 is the Lorentz factor, 𝑚 and 𝜈 are the ion mass and velocity, respectively.

During the experiment described in this dissertation, the magnet chamber was filled with 0.5 Torr of helium (He) gas which provided charge equilibration of fusion-evaporation reaction products. This results in the narrower distribution of the product's magnetic rigidity and much higher transmission through the separator compared to vacuum devices which can accept only up to two charge states [START_REF] Ressler | SASSYER: An Old Instrument for New Physics at Yale[END_REF][START_REF] Folden | Characterization of the Aggie Gas-Filled Separator[END_REF].

The magnetic fields of two dipole magnets D1 and D2 were tuned to bend the ions through the separator along the central axis. At the same time, the unreacted beam particles, which had a lower magnetic rigidity and lower radius of curvature, were stopped and collected in a beam dump box [START_REF] Ressler | SASSYER: An Old Instrument for New Physics at Yale[END_REF] located in front of the D1 magnet as shown in Figure 17. The magnetic field of a quadrupole magnet Q1 was tuned to bend the ions through the separator away from the central axis. Therefore, the separation of ions from the primary beam can be achieved following the target.

Simple Recoil Transfer Chamber

A simple Recoil Transfer Chamber (sRTC), composed of a funnel and a detector chamber, has been designed and used for the first time. Figure 17 illustrates the sRTC installed on the AGGIE separator. Figure 18 shows a closer view of the components of the sRTC and its crosssectional view. The goal of the sRTC is to stop the ions of interest in the funnel by their collision with atoms of helium gas (350 Torr) which goes through the sRTC with a flow of 500-1800 standard cubic centimeters per minute. In turn, this enables more efficient sorption and detection of the named nuclides on the non-modified and modified silicon detectors located in the detector chamber. To separate the volumes of the sRTC and the separator operating at different pressures, an aluminized Mylar window (2 μm) was mounted at the entrance of the sRTC which is displayed in Figure 18 and Figure 19.

Aluminized Mylar window

In addition, a rotating degrader made of Mylar (4 μm) was installed upstream of the sRTC inside the T connector; its location is indicated by a blue arrow in Figure 17. Changing the angle of the rotating degrader (0-75 degrees) results in the increase or decrease of the effective thickness of the material (4.0-15.5 μm) the ions are going through. As a result, it was possible to select a rotating degrader angle at which the ions were stopped mostly in the funnel due to their energy loss while traveling through the rotating degrader material of the corresponding thickness and an aluminized Mylar window. Consequently, this increased the count rate of a produced nuclide.

Detector Chamber

The detector chamber inside the sRTC depicted in Figure 18 After this, Im-C11-SH or MDDA SAMs were deposited on two gold-coated silicon detectors from 5 mM ethanolic solutions of the corresponding thiols. Before depositing thiol solutions onto the surface of detectors, they need to be precleaned to get rid of any adventitious organic molecules present on the surface of gold. For that, two gold-coated silicon detectors were placed in a Petri dish and exposed to UV light of the UV-sterilizer for 1.5 h. Then, the surface of gold was washed with a deoxygenated ethanol solution approximately 10 times using a glass Pasteur pipette and a so-called "chimney" illustrated in Figure 20 that was designed for this study.

The substrate pretreatment technique that involves adding the H2O2 solution onto the detector surface coupled with the UV light exposure was found to damage the surface of gold by peeling it off completely. As a result, H2O2 was excluded from the precleaning technique leaving only the UV light factor. The preparation of ethanolic thiol solutions is identical to that described in Section 2.3.1.2. An aliquot of 3 mL of 5 mM Im-C11-SH or MDDA ethanolic solution was added onto the detector surface using a "chimney". It allowed a thiol solution to be in contact only with the detector surface preventing damaging the detector if it was submerged into the solution. The "chimney" was sealed with a cap wrapped with Parafilm to avoid exposure to air, and aluminum foil was wrapped around the "chimney" to avoid exposure to light. The thiol solution was left in contact with the detector surface for 21 h. The SAMs deposition was performed twice to obtain the highest surface coverage. So, the next day, the thiol solution was poured into the thiol waste, and the detector surface was washed with an ethanol solution approximately 10 times using a glass Pasteur pipette and the "chimney". To dry the detector surface, a stream of compressed Ar gas was used. To remove the SAMs before the second deposition, the detector was exposed to UV light for 2 h.

Photooxidation of SAMs by exposure to UV light has already been studied before [START_REF] Yan | Modification of Alkanethiolate Self-Assembled Monolayers by Ultraviolet Light: The Effect of Wavelength[END_REF][START_REF] Brewer | Photooxidation of Self-Assembled Monolayers by Exposure to Light of Wavelength 254 nm: A Static SIMS Study[END_REF]. It was suggested that UV-induced so-called "hot" electrons tunnel from the gold substrate to the empty electronic states of the sulfur atoms which initiates their excitation and the formation of anionic radicals [START_REF] Yan | Modification of Alkanethiolate Self-Assembled Monolayers by Ultraviolet Light: The Effect of Wavelength[END_REF][START_REF] Brewer | Photooxidation of Self-Assembled Monolayers by Exposure to Light of Wavelength 254 nm: A Static SIMS Study[END_REF]. In turn, they react with oxygen molecules that penetrate the SAMsubstrate interface and form sulfinates as a result [START_REF] Yan | Modification of Alkanethiolate Self-Assembled Monolayers by Ultraviolet Light: The Effect of Wavelength[END_REF][START_REF] Brewer | Photooxidation of Self-Assembled Monolayers by Exposure to Light of Wavelength 254 nm: A Static SIMS Study[END_REF]. Sulfinates can disproportionate or be oxidized to sulfonates which can be washed away with ethanol followed by the release of alkyl chains [START_REF] Johnson | Regeneration of Gold Surfaces Covered by Adsorbed Thiols and Proteins Using Liquid-Phase Hydrogen Peroxide-Mediated UV-Photooxidation[END_REF][START_REF] Yan | Modification of Alkanethiolate Self-Assembled Monolayers by Ultraviolet Light: The Effect of Wavelength[END_REF][START_REF] Brewer | Photooxidation of Self-Assembled Monolayers by Exposure to Light of Wavelength 254 nm: A Static SIMS Study[END_REF]. The SAMs photooxidation mechanism proposed by Yan et al. [START_REF] Yan | Modification of Alkanethiolate Self-Assembled Monolayers by Ultraviolet Light: The Effect of Wavelength[END_REF] is depicted in Figure 21.

The next step after the SAMs removal was to wash the detector surface with a deoxygenated ethanol solution approximately 10 times as described above. Then, an aliquot of 3 mL of 5 mM Im-C11-SH or MDDA ethanolic solution was added onto the detector surface using a "chimney" for the second time. After 21 h of the SAMs deposition, the thiol solution was poured into the thiol waste. The detector surface was washed with a deoxygenated ethanol solution approximately 10 times as it was described above and dried using a stream of compressed Ar gas.

The functionalized gold-coated silicon detectors were placed into the detector chamber.

Alpha Spectrometry

Alpha spectrometry was performed to measure the resolution of the silicon detectors before and after their coating with gold, as well as after using the functionalized gold-coated silicon detectors during online cyclotron-based experiments. A model 7401 single channel alpha spectrometer with a Multiport II MCA illustrated in Figure 22 was calibrated against a NISTtraceable four-peak alpha calibration source containing 148 Gd, 239,240 Pu, 241 Am, and 244 Cm. As will be discussed later, the chips were tested on whether they can be reused by using the liquid-UVPO treatment [START_REF] Johnson | Regeneration of Gold Surfaces Covered by Adsorbed Thiols and Proteins Using Liquid-Phase Hydrogen Peroxide-Mediated UV-Photooxidation[END_REF] to remove SAMs, and depositing SAMs for the second time. The Image Rq value of the named substrate is 1.25 nm as depicted in Figure 23c. The comparison of the similar AFM images and the Image Rq values, which remain in the same range, suggests that the first and the second SAMs depositions, as well as the liquid-UVPO treatment, do not produce a macroscopic change to the surface morphology and topography, and as a result, the substrates can be reused without noticeable surface damage.

In the corresponding 2×2 μm AFM images provided in Figure 24, the grains of gold can be observed. One needs to pay attention to the zoomed-in region of 252.5-255.5 amu in Figure 26a,b.

The important characteristic peak of an (Im-C11-S -) fragment at 253. deprotonated molecule of Im-C11-SH which implies that the adsorption process occurred on the surface of gold [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF].

It must be noted that for the substrate shown in Figure 26a, the concentration of an Im-C11-SH solution was 1.6 mM, whereas, in Figure 26b, it was increased to 5 mM. As a result, the intensity of the (Im-C11-S -) peak increased with an increase in the thiol concentration. This is one of the pieces of evidence that the coverage increased.

Also, in Figure 26a, the surface of Au was not precleaned using the liquid-UVPO treatment before the SAMs deposition. The positive impact of this treatment can be observed by comparing spectra in Figure 26a after the liquid-UVPO treatment was used. This technique was selected for all further experiments due to its efficacy, and its promising preservation of surface morphology as well as crystallinity of Au [START_REF] Johnson | Regeneration of Gold Surfaces Covered by Adsorbed Thiols and Proteins Using Liquid-Phase Hydrogen Peroxide-Mediated UV-Photooxidation[END_REF].

To measure the coverage (K) of Au-coated Si chips with Im-C11-SH SAMs, the Surface Analysis and Mapping of Projectile Impacts (SAMPI©) software (version 5.0.5) was employed [START_REF] Eller | SIMS Instrumentation and Methodology for Mapping of Co-Localized Molecules[END_REF]95]. A characteristic pair of Au-S cluster ions, namely Au2S -(426 amu) and Au3S -(623 amu), was selected to perform calculations. The SAMPI© software enables the extraction of the total number of detected ions per impact (Ytot, the total yield) from a total spectrum, and the number of detected ions per impact when detecting a specific ion (Ycoinc, the coincidence yield) from a coincidence spectrum. In general, a coincidence spectrum is composed of events containing a selected ion of interest. It shows all ions co-emitted with the selected ion from the same desorption volume [94,95,[START_REF] Liang | Size-Dependent Emission of Negative Ions from Gold Nanoparticles Bombarded with C60 and Au400[END_REF][START_REF] Park | Coincidence Counting in Time-of-Flight Mass Spectrometry: A Test for Chemical Microhomogeneity[END_REF][START_REF] Verkhoturov | Nanoprojectile Secondary Ion Mass Spectrometry for Analysis of Extracellular Vesicles[END_REF][START_REF] Eller | Nanoprojectile Secondary Ion Mass Spectrometry for Nanometrology of Nanoparticles and Their Interfaces[END_REF]. In the present case, impacts of the detected Au3S -ions were selected to obtain a coincidence spectrum, after which the total yield of the co-emitted Au2S -ion, Ytot (Au2S -), was divided by the coincidence yield of Au2S -ion, Ycoinc (Au2S -). The corresponding peaks are shown in Figure 27a, 28a. To sum up, K was measured utilizing the following equation:

𝐾 = 𝑌 𝑡𝑜𝑡 (𝐴𝑢 2 𝑆 -) 𝑌 𝑐𝑜𝑖𝑛𝑐 (𝐴𝑢 2 𝑆 -)
• 100% Eq. 5

K was measured to be (78 ± 7)% when the SAMs deposition was performed from a 1.6 mM Im-C11-SH solution for the first time.

To increase the K value, the concentration of ethanolic Im-C11-SH solution was increased to 5 mM during the second deposition. Impacts of the detected Au3S -(623 amu), Au(Im-C11-S -)2

(703 amu, and 704 amu due to the presence of 13 C), Au4S -(820 amu), and Au5S -(1017 amu) ions were selected to obtain a sum coincidence spectrum. The corresponding peaks are depicted in Figure 28b. In general, a sum coincidence spectrum is composed of events containing either of the selected ions of interest. Such selection enhances the accuracy of co-localized species identification on complex surfaces [94,95]. To measure K, the total yield of Au2S -ion was divided by the coincidence yield of Au2S -ion utilizing Eq. 5. The corresponding peak is shown in Figure 27b. The K value was increased to (99 ± 6)%.

Moreover, the appearance of another characteristic peak of a dimer Au(Im-C11-S -)2 at 703 amu in Figure 28b confirms that the coverage increased for the sample with the higher thiol concentration. The reason is that this peak corresponds to the fragment where two deprotonated molecules of Im-C11-SH are attached to the same gold center.

Additionally, one more confirmation that the coverage increased is we observed a decrease in the peak intensities corresponding to the substrate signal Au -, and gold cluster ions Aux -shown in Figure 26b The main conclusions of NP-SIMS are: 1) a chip needs to be precleaned using the liquid-UVPO treatment before the SAMs deposition from a 5 mM ethanolic thiol solution;

2) The highest value of the coverage was obtained in the order of (99 ± 6)% after the second SAMs deposition which indicates that surface is covered with Im-C11-SH SAMs quantitatively. To sum up, to obtain the highest coverage, one cycle of SAMs deposition-regeneration is recommended before the final second deposition. Sulfur XPS spectra shown in Figure 29 contain spin-orbit splitting components with S 2p3/2 at around 162.5 eV which corresponds to a thiolate bound to the gold surface, while S 2p1/2 at 163.0-164.0 eV indicates some unbound sulfur species produced due to the damage of SAMs caused by the ionizing radiation (X-rays during XPS measurements, or UV-light during the liquid-UVPO treatment) [START_REF] Kato | Strong Hydrogen Bonds at the Interface between Proton-Donating and -Accepting Self-Assembled Monolayers on Au(111)[END_REF][START_REF] Willey | Rapid Degradation of Alkanethiol-Based Self-Assembled Monolayers on Gold in Ambient Laboratory Conditions[END_REF][START_REF] Zharnikov | Modification of Thiol-Derived Self-Assembling Monolayers by Electron and X-ray Irradiation: Scientific and Lithographic Aspects[END_REF][START_REF]XPS Reference Table of Elements[END_REF].

Nitrogen XPS spectra are presented in Figure 30 for the same series of samples. They contain two components in N 1s peaks at 399.42 and 401.19 eV, which are assigned to imino and amino N of the imidazole ring in the Im-C11-SH molecule (see Figure 1a in Section 2.3.1.2) [START_REF] Kato | Strong Hydrogen Bonds at the Interface between Proton-Donating and -Accepting Self-Assembled Monolayers on Au(111)[END_REF][START_REF] Feyer | Adsorption of Histidine and a Histidine Tripeptide on Au(111) and Au(110) from Acidic Solution[END_REF][START_REF] Offord | Synthesis and Properties of Metalloporphyrin Monolayers and Stacked Multilayers Bound to an Electrode Via Site Specific Axial Ligation to a Self-Assembled Monolayer[END_REF].

As can be seen in Figure 29b,30b and Table 8, the peaks of S 2p and N 1s vanished after the H2O2-mediated liquid UV-light photooxidation treatment that was employed to remove thiolate SAMs. Additionally, increases in the Au 4f peak area shown in Table 8 and the Au 4f peak intensity (see Figure A1a,b in the appendix) further support this idea. So, when SAMs are removed, the gold photoelectrons are no longer attenuated which rises the intensity of Au 4f peaks [START_REF] Willey | Rapid Degradation of Alkanethiol-Based Self-Assembled Monolayers on Gold in Ambient Laboratory Conditions[END_REF]. The percentages of S 2p, C 1s, and N 1s peaks decrease drastically after Im-C11-SH SAMs are removed as seen in Table 8. The S 2p, C 1s, and N 1s peak intensities and areas are related to the amount of Im-C11-SH SAMs present on the gold surface. Decreases in the intensities, the peak areas, and the composition percentage explain Im-C11-SH SAMs desorption [START_REF] Willey | Rapid Degradation of Alkanethiol-Based Self-Assembled Monolayers on Gold in Ambient Laboratory Conditions[END_REF]. Carbon and oxygen XPS spectra are illustrated in Figure A1 in the appendix. The S 2p peak area of the freshly prepared Im-C11-SH SAMs was assumed to be 100%. Then, solving the proportion showed that 80% of SAMs were desorbed from the gold surface. This all suggests that the gold-coated silicon chips can be reused.

The process that stands behind the removal of SAMs from the gold surface is the following.

After the UV light interacts with H2O2, hydroxyl radicals (HO • ) are formed. Then, thiolate species are oxidized to sulfonates that loosely bind to metal surfaces and can be easily washed away with ethanol [START_REF] Johnson | Regeneration of Gold Surfaces Covered by Adsorbed Thiols and Proteins Using Liquid-Phase Hydrogen Peroxide-Mediated UV-Photooxidation[END_REF]:

½ H2O2 + h𝜈 → HO • Eq. 6 RS-Au + O2 + HO • → RSO3H + Au, Eq. 7
where R is the organic radical. Several pathways of imidazole atmospheric oxidation initiated by hydroxyl radicals can be found in the study conducted by Safaei et al. [START_REF] Safaei | Atmospheric Oxidation Reactions of Imidazole Initiated by Hydroxyl Radicals: Kinetics and Mechanism of Reactions and Atmospheric Implications[END_REF].

Furthermore, the effect of sample aging was studied. The XPS results indicate that prepared SAMs do not degrade significantly when stored under ambient conditions, except that samples were stored in wafer carrier trays and wrapped with aluminum foil to avoid exposure to air and light. These are known to be the main factors in the SAMs degradation [START_REF] Willey | Rapid Degradation of Alkanethiol-Based Self-Assembled Monolayers on Gold in Ambient Laboratory Conditions[END_REF]. The decrease in the S 2p peak areas allows us to evaluate the kinetics of the Im-C11-SH SAMs degradation. Therefore, 3% and 9% of SAMs were lost after two weeks and one month of storage, respectively.

Additionally, a shoulder that corresponds to the imino N component becomes less pronounced after the sample storage which is presented in Figure 30c,d. This can be attributed to the transformations inside the imidazole ring due to atmospheric oxidation which was previously reported by Safaei et al. [START_REF] Safaei | Atmospheric Oxidation Reactions of Imidazole Initiated by Hydroxyl Radicals: Kinetics and Mechanism of Reactions and Atmospheric Implications[END_REF]. On the other hand, the Au 4f peak areas listed in Table 8 and the Au 4f peak intensities (see Figure A1 in the appendix) increase during the sample storage which also means that a lower amount of the thiolate molecules is present on the gold surface. At the same time, Table 8 shows that the C 1s peak areas increase slightly. This might be attributed to the contamination of the gold surfaces with organic compounds detached from the walls of the wafer carrier trays. Table 8 also reveals the same trend for the elemental composition of SAMs.

Degradation of thiolate SAMs under ambient conditions leads to the formation of either disulfides (Eq. 8) or sulfonates (Eq. 9) which can be easily washed away from the gold surface with ethanol [START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF][START_REF] Cortés | Enhanced Stability of Thiolate Self-Assembled Monolayers (SAMs) on Nanostructured Gold Substrates[END_REF][START_REF] Yang | Molecular-Level Approach to Inhibit Degradations of Alkanethiol Self-Assembled Monolayers in Aqueous Media[END_REF]:

2 RS-Au → RSSR + 2 Au Eq. 8

RS-Au + H2O + O3 → RSO3H + HO-Au Eq. 9

Even though such oxidation factors as air and light were limited, even a small amount of moisture present in closed wafer-carrier trays could lead to the beginning of the SAMs partial degradation processes.

Similarly, the chemical state of MDDA SAMs deposited from a 5 mM ethanolic thiol solution once was characterized by XPS. Sulfur XPS spectra shown in Figure 31 [START_REF]XPS Reference Table of Elements[END_REF], [START_REF] Gupta | Synthesis of 16-Mercaptohexadecanoic Acid Capped Gold Nanoparticles and their Immobilization on a Substrate[END_REF]. The last two components are attributed to the presence of the carboxyl functional group in the MDDA structure (see Figure 1b in Section 2.3.1.2). Table 9 summarizes Au 4f, C 1s, O 1s, S 2p peak areas as well as the elemental composition of SAMs. Gold and oxygen XPS spectra are illustrated in the appendix. Likewise, the effect of sample aging was studied under the same storage conditions as for Im-C11-SH SAMs. Minor changes in the shape of the S 2p doublet peak shown in Figure 31 and the S 2p peak area listed in Table 9 as a function of the sample storage time indicate the nonsignificant degradation of MDDA SAMs. The Au 4f peak area also remained in the same range after one week of the sample storage as shown in Table 9. Slight increases in the Au 4f peak area and the Au 4f peak intensity (see Figure A2 in the appendix) after one month of the sample storage mean that some MDDA SAMs were desorbed from the surface of gold making the gold photoelectrons no longer attenuated [START_REF] Willey | Rapid Degradation of Alkanethiol-Based Self-Assembled Monolayers on Gold in Ambient Laboratory Conditions[END_REF]. The C 1s peak intensity presented in Figure 32 and the C 1s peak area listed in Table 9 decrease slightly after one month of the sample storage also supporting the idea of the insignificant MDDA SAMs degradation.

Measurement of the thickness of Im-C11-SH SAMs

Ellipsometry is an optical spectroscopy technique that was used to determine the thickness of Im-C11-SH SAMs deposited from a 5 mM ethanolic thiol solution once. SAMs are very thin organic layers that are ideally composed of a single monolayer [START_REF] Woollam Co | CompleteEASE TM Data Analysis Manual[END_REF]. In general, their thickness is in the order of 1-2 nm and not more than 10 nm [START_REF] Prato | Optical Characterization of Thiolate Self-Assembled Monolayers on Au(111)[END_REF][START_REF] Bain | Formation of Monolayer Films by the Spontaneous Assembly of Organic Thiols from Solution onto Gold[END_REF][START_REF] Offord | Synthesis and Properties of Metalloporphyrin Monolayers and Stacked Multilayers Bound to an Electrode Via Site Specific Axial Ligation to a Self-Assembled Monolayer[END_REF][START_REF] Woollam Co | CompleteEASE TM Data Analysis Manual[END_REF].

Ellipsometry is sensitive to the presence of thin SAMs on the surface of gold due to the change in the measured delta (∆) parameter, which contains information about the phase difference between p-and s-polarized light [140]. The measured (square symbols) and modeled (solid curves)

∆ values versus the wavelength (𝜆) are plotted in full scale in Figure 33a. In the zoomed-in region of low delta values represented in Figure 33b, the change between samples can be observed.

During ellipsometry measurements, it is important to measure a bare gold surface to determine optical constants at first. The obtained data shown as green square symbols in Figure 33 was fitted using a B-Spline layer. As a result, the modeled green solid curve in Figure 33 represents the bare precleaned gold surface.

After this step, the thickness of the thin organic layer (Im-C11-SH SAMs in our case) can be measured. The blue square symbols in Figure 33b represent Im-C11-SH SAMs on the precleaned gold surface. One can notice a vertical shift in ∆ toward lower values which is attributed to the presence of a thin film on top of gold. In the case of thicker films on the gold surface, a larger shift is observed. By fitting the data using the Cauchy layer, the blue solid curve was obtained, and the thickness of 1.690 ± 0.014 nm was reported for the freshly deposited Im-C11-SH SAMs.

The thickness of Im-C11-SH SAMs on the precleaned gold surface was also measured after one week of sample storage represented by the red square symbols in Figure 33b. The red solid curve was obtained after fitting the data, and the thickness of 1.640 ± 0.011 nm was measured.

The thickness value is slightly lower than that for the freshly deposited SAMs, but the difference in values is practically non-significant. Figure 33b also demonstrates the proximity of the fits for the freshly deposited and one-week-old SAMs. As a result, ellipsometry showed that storing Im-C11-SH SAMs for one week did not initiate degradation processes which would lead to a decrease in the SAMs thickness.

The measured thickness values indicate the presence of a single monolayer on the surface of gold and are in good agreement with the literature results obtained for similar films [START_REF] Prato | Optical Characterization of Thiolate Self-Assembled Monolayers on Au(111)[END_REF][START_REF] Bain | Formation of Monolayer Films by the Spontaneous Assembly of Organic Thiols from Solution onto Gold[END_REF][START_REF] Offord | Synthesis and Properties of Metalloporphyrin Monolayers and Stacked Multilayers Bound to an Electrode Via Site Specific Axial Ligation to a Self-Assembled Monolayer[END_REF]. In the NP-SIMS analysis, a primary beam of 520 keV Au400 4+ clusters bombards the surface of the functionalized chips, and the energy transfer from the beam to the surface causes the emission of cluster ions [START_REF] Eller | Testing Molecular Homogeneity at the Nanoscale with Massive Cluster Secondary Ion Mass Spectrometry[END_REF]94]. In Figure 34b-d, one should notice that the intensities of the named clusters are much higher for samples where the Rh(III) sorption occurred on gold-coated glass chips functionalized with Im-C11-SH SAMs compared to non-functionalized ones. For instance, the sum net yield for the peaks corresponding to RhCl3 -clusters (208-214 amu) observed on precleaned Au functionalized with Im-C11-SH SAMs, and precleaned Au without Im-C11-SH SAMs is 1.73•10 -2 , and 1.85•10 -3 , respectively. The net yield is the total yield with the background subtraction. The difference of one order of magnitude indicates more quantitative Rh(III) sorption on functionalized gold-coated glass chips rather than on non-functionalized ones.

RhCl3 -was chosen as a primary cluster to measure the coverage of Im-C11-SH SAMs with Rh(III). The named cluster will give a more accurate result since its peaks are more narrow and have no significant interference compared to the RhCl4 -group of peaks which have more interference with other ions, such as AuCNC2 -(247 amu), AuCNC2H -(248 amu) shown in Figure 34c. RhCl5 -and Rh2Cl7 -clusters were not taken into consideration for the coverage calculation due to low statistics.

To measure K of Im-C11-SH SAMs with Rh(III), a similar approach described above to measure K of Au-coated Si chips with Im-C11-SH SAMs was used [94,95,[START_REF] Liang | Size-Dependent Emission of Negative Ions from Gold Nanoparticles Bombarded with C60 and Au400[END_REF][START_REF] Park | Coincidence Counting in Time-of-Flight Mass Spectrometry: A Test for Chemical Microhomogeneity[END_REF][START_REF] Verkhoturov | Nanoprojectile Secondary Ion Mass Spectrometry for Analysis of Extracellular Vesicles[END_REF][START_REF] Eller | Nanoprojectile Secondary Ion Mass Spectrometry for Nanometrology of Nanoparticles and Their Interfaces[END_REF]. At first, impacts were selected where Rh 35 Cl2 37 Cl -ion (210 amu) was detected to obtain a coincidence spectrum. After this, the total yield of co-emitted Rh The results are represented in Table 10. In the Rh(III) sorption experiments, the coverage of Au with Im-C11-SH SAMs was measured according to Eq. 5 and gave a result of (80 ± 5)%. The SAMs deposition was performed once.

The presence of characteristic peaks of IrCl3 -(296-302 amu), IrCl4 -(331-339 amu), Ir2Cl4 - Ir2Cl6 -was chosen as a primary cluster to measure the coverage of Im-C11-SH SAMs with Ir(IV). The named cluster will give a more accurate result since by itself it can form Ir2Cl4 -and Ir2Cl5 -clusters during the fragmentation. Also, its intensity is much higher than that for Ir2Cl7 - which is observed in Figure 35c. IrCl3 -, IrCl4 -, Ir3Cl9 -and Ir3Cl10 -clusters were not taken into consideration for the calculation of K due to low statistics.

At first, impacts, where Ir2Cl4 -(522-534 amu) or Ir2Cl5 -(557-571 amu) ions were detected, were selected to obtain a sum coincidence spectrum. As it was discussed earlier, such selection enhances the accuracy of co-localized species identification on complex surfaces [94,95]. The peaks with the low mass intensity were not taken into consideration. After this, the total yield of co-emitted Ir2Cl6 -ion (596 amu), Ytot (Ir2Cl6 -), was divided by the coincidence yield of Ir2Cl6 -ion,

Ycoinc (Ir2Cl6 -): 𝐾 = 𝑌 𝑡𝑜𝑡 (𝐼𝑟 2 𝐶𝑙 6 -) 𝑌 𝑐𝑜𝑖𝑛𝑐 (𝐼𝑟 2 𝐶𝑙 6 -) • 100% Eq. 11
The results are represented in Table 11. In the Ir(IV) sorption experiments, the coverage of Au with Im-C11-SH was measured to be (90 ± 5)% according to Eq. 5. The SAMs deposition was performed once. A doubly charged complex [IrCl6] 2-is a predominant species in an aqueous solution [START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF][START_REF] Zakusilova | Extraction and Separation of Iridium(IV) and Rhodium(III) from Hydrochloric Acid Media by a Quaternary Ammonium-Based Hydrophobic Eutectic Solvent[END_REF]. Therefore, its molar mass was used to measure the number of Ir(IV) molecules in the aqueous phase.

The surface saturation (SS) of Im-C11-SH SAMs with Ir(IV) was measured using the following equation:

𝑆𝑆 = 𝑁 𝐼𝑟 init -𝑁 𝐼𝑟 eq 𝐴 • 𝑁 SAMs • 100%, Eq. 12
where 𝑁 𝐼𝑟 init is the initial number of Ir(IV) molecules in solution before sorption;

𝑁 𝐼𝑟 eq is the number of Ir(IV) molecules in solution after sorption;

A is the area of a chip that is equal to 1 cm 2 ;

𝑁 SAMs which equals 4.510 14 molecules/cm 2 is the typical surface density of molecules for alkanethiolate SAMs when the maximum coverage is obtained [START_REF] Love | Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology[END_REF]. INAA results for functionalized and non-functionalized gold-coated chips are summarized in Table 12 and Table 13, respectively. Ir(IV) was barely adsorbed on precleaned gold-coated chips without SAMs which can be seen in Table 13, the highest surface saturation of <20% was observed at 5.4 μM initial Ir(IV) concentration. Additionally, the gamma-ray branching ratio for 104m Rh, which is 48% [START_REF] Blachot | Nuclear Data Sheets for A = 104[END_REF], is much lower than that for 192 Ir which is 83% [START_REF] Baglin | Nuclear Data Sheets for A = 192[END_REF]. All of the mentioned above explain the increased uncertainties during Rh measurements.

Conclusion

In this work, the surface characterization of gold-coated silicon chips functionalized with

Online Сyclotron-Based Experiments

The results of the experiment aimed at three fusion-evaporation reactions:

Radionuclide detection on non-functionalized and functionalized silicon detectors

The effect of the detector position in the detector chamber, and the detector material on the 152,153 Er, 199-201 At, and 173-176 Ir rates was investigated. The materials tested were bare silicon (Bare Si), gold-coated silicon (Si+Au), gold-coated silicon functionalized with Im-C11-SH SAMs

Multiple-peak Fit Analysis

The obtained 152,153 Er, 199-201 At, and 173-176 Ir spectra shown in Figure 42, Figure 44, and Figure 46 as black histograms contain wide peaks. This suggests that several components might be present: products of a performed nuclear reaction, as well as their decay products whose 𝛼-decay lines overlap. The multiple-peak fit makes it possible to distinguish the components by fitting them individually [START_REF] Götz | Rapid Extraction of Short-Lived Isotopes from a Buffer Gas Cell for Use in Gas-Phase Chemistry Experiments, Part II: On-Line Studies with Short-Lived Accelerator-Produced Radionuclides[END_REF]. In the present case, an asymmetric double-sigmoidal function was used in Origin® to fit the experimental data, and individual peaks of nuclides were obtained as depicted in Figure 42, Figure 44, and Figure 46.

89

The asymmetric double-sigmoidal function is defined as:

𝑦 = 𝑦 𝑜 + 𝐴 • 1 1+𝑒 - 𝑥-𝑥 𝑐 + 𝜔 1 2 𝜔 2 • (1 - 1 1+𝑒 - 𝑥-𝑥 𝑐 - 𝜔 1 2 𝜔 3
),

Eq. 13

where 𝑦 𝑜 is the offset, 𝑥 𝑐 is the centroid of a nuclide peak, 𝐴 is the amplitude, 𝜔 1 is the full width at half maximum, 𝜔 2 is the variance of the low-energy side, 𝜔 3 is the variance of the highenergy side. 𝜔 1 , 𝜔 2 , 𝜔 3 are the width parameters that were determined from calibration spectra of 152,153 Er, 199-201 At, and 173-176 Ir.

A calibration spectrum for 152,153 Er shown in Figure 39 as a black histogram was collected on the Bare Si detector that was placed vertically in the detector chamber. The detector surface is perpendicular to the trajectory of produced ions of interest in such a position. The rotating degrader was set to 80 degrees. The sRTC was kept under a vacuum. All of these settings give the possibility to observe the highest count rate of 152,153 Er. Utilizing Eq. 13, the best fit was obtained when centroids of a parent nuclide and its 𝛽 + -decay daughter nuclide were selected: 4804 keV for 152 Er and 4386 keV for 152 Ho, respectively [START_REF] Nica | Nuclear Data Sheets for A = 148[END_REF]. The solid green and orange curves represent individual 𝛼-decay lines of the named nuclides, respectively. The solid pink curve is the cumulative fit peak which is in good agreement with the original histogram. Fitting the calibration spectrum allowed the three width parameters to be determined as listed in A calibration spectrum for 199-201 At shown in Figure 40 as a black histogram was collected on the Bare Si detector that was placed vertically in the detector chamber. The rotating degrader was set to 90 degrees. The sRTC was kept under a vacuum. Utilizing Eq. 13, the best fit was obtained when centroids of parent nuclides were selected: 6342 keV for 201 At [START_REF] Xiaolong | Nuclear Data Sheets for A=197[END_REF], 6465 keV for 200 At [START_REF] Xiaolong | Nuclear Data Sheets for A = 196[END_REF], and 6643 keV for 199 At [START_REF] Xiaolong | Nuclear Data Sheets for A = 195[END_REF]. The solid green, blue, and orange curves represent individual 𝛼-decay lines of the named nuclides, respectively. The solid pink curve is the cumulative fit peak which is in good agreement with the original histogram. The three width parameters were determined as listed in Table 15.

centroid was not selected for fitting [START_REF] Nica | Nuclear Data Sheets for A = 148[END_REF]. The nuclear reaction 141 Pr( 40 Ar, 5n) 176 Ir was performed after 118 Sn( 40 Ar, 5n) 153 Er, this is why the long-lived nuclides 149 Tb and 152 Dy with half-lives of 4.118±0.025 h [START_REF] Browne | Nuclear Data Sheets for A = 145[END_REF] and 2.38±0.02 h [START_REF] Nica | Nuclear Data Sheets for A = 148[END_REF], respectively, can be observed in the 173-176 Ir spectra.

The three width parameters obtained after the multiple-peak fit analysis of the Fixing the determined width parameters and the centroids of possible nuclides present in a spectrum being analyzed allows to perform the multiple-peak fit and obtain individual 𝛼-decay lines as a result. The fitted 152,153 Er, 199-201 At, and 173-176 Ir spectra are shown in Figure 42, Figure 44, and Figure 46 and discussed in the next section.

3.4.1.2 152,153 Er detection on non-functionalized and functionalized silicon detectors

Figure 42 shows the 152,153 Er spectra as black histograms collected on the Bare Si and the Si+Au detectors in configuration A with the rotating degrader at 55 degrees. At such an angle, the highest rate of 152,153 Er was detected. The multiple-peak fit analysis of these spectra allowed to distinguish the peaks of parent nuclides: 153 Er at 4674 keV [START_REF] Singh | Nuclear Data Sheets for A=149[END_REF] and 152 Er at 4804 keV [START_REF] Nica | Nuclear Data Sheets for A = 148[END_REF], as well as their decay products. The 153 Er long-lived granddaughter nuclide, 149 Tb, at 3967 keV is observed. Also, the 153 Er 𝛽 + -decay daughter nuclide, 153 Ho, at 3910 keV might be observed, but the 𝛼-branching ratio is only 0.05% for which reason this nuclide's centroid was not selected for fitting. Lastly, the peak of the 152 Er 𝛽 + -decay daughter nuclide, 152 Ho, at 4386 keV was distinguished as well. The solid blue, orange, red, and green curves represent individual 𝛼-decay lines of the named nuclides, respectively.

The pink curve is the cumulative peak which is in good agreement with the original histogram. The 𝛼-decay information for the studied nuclides and the width parameters used to perform the multiple-peak fit analysis are presented in Table 16. The width parameters were determined from the 152 Er calibration spectrum and shared for all peaks within the analyzed spectrum. Likewise, the fit was performed for two other spectra collected on the MDDA and the C11-Im detectors within this configuration, as well as all for spectra collected in three other

Eq. 21

The results are summarized Table 17 and Figure 43. The 3D plot depicted in Figure 43 200 At, and 199 At counts by the mean of Rutherford scattering events. The calculation was performed utilizing Eq. 14-16. The results are summarized in Table 19 and Figure 45.

Table 19. 199-201 At rate obtained on detectors with four different materials at four different positions.

Bare Si MDDA Si+Au C11-Im Sum 𝑅,

•10 -4 𝛿𝑅,

•10 -4 𝑅,

•10 -4 𝛿𝑅,

•10 -4 𝑅,

•10 -3 𝛿𝑅,

•10 -3 𝑅,

•10 -4 𝛿𝑅,

•10 -4 𝑅,

•10 -3 𝛿𝑅,

•10 Figure 46 shows the 173-176 Ir spectra as black histograms collected on the Bare Si and the Si+Au detectors in configuration D with all rotating degrader angles summed up. It means that for each of the named detectors, 173-176 Ir spectra collected at every rotating degrader angle were summed up to obtain a final spectrum. The summation was done to enable the fitting of the data with low statistics. The multiple-peak fit analysis of these spectra made it possible to distinguish the peaks of parent nuclides: 5118 keV for 176 Ir [START_REF] Singh | Nuclear Data Sheets for A = 172[END_REF], 5275 keV for 174 Ir [START_REF] Baglin | Nuclear Data Sheets for A=170[END_REF], and 5406 keV for 173,175 Ir [START_REF] Baglin | Nuclear Data Sheets for A = 169[END_REF][START_REF] Baglin | Nuclear Data Sheets for A=171[END_REF]. Also, the peak at 3967 keV is attributed primarily to 149 Tb which is a granddaughter nuclide of 153 Er [START_REF] Browne | Nuclear Data Sheets for A = 145[END_REF] which was produced during a previous experiment. The peak of 152 Dy, which is a 𝛽 + -decay granddaughter nuclide of 152 Er, at 3628 keV might also be observed, but the 𝛼-branching ratio is only 0.1% [START_REF] Nica | Nuclear Data Sheets for A = 148[END_REF]. The solid green, blue, orange, and red curves represent individual 𝛼-decay lines of the named nuclides, respectively. The pink curve is the cumulative peak which is in good agreement with the original histogram. The peak that is attributed to 149 Tb (red curve) is overlapping with the cumulative fit peak, as a result, it is represented by the pink curve.

The 𝛼-decay information for the studied nuclides and the width parameters used to perform the multiple-peak fit analysis are presented in Table 15. The width parameters determined from the 152,153 Er calibration spectrum were used to fit the 173-176 Ir spectra and shared for all peaks within the analyzed spectrum. As it was discussed in Section 3.4.1.1, the width parameters could not be determined from the 173-176 Ir calibration spectrum due to low statistics. Likewise, the fit was performed for two other spectra collected on the MDDA and the C11-Im detectors within this configuration, as well as all for spectra collected in three other configurations with all rotating degrader angles summed up.

Similar to the 152,153 Er and the 199-201 At data analyses, the peak areas of 176 Ir, 174 Ir, and 173,175 Ir, obtained after the integration of the corresponding peaks were divided by the bin width (40 keV in this case) to calculate the number of counts for 176 Ir, 174 Ir, and 173, 175 Ir separately. The bin width was increased due to low statistics. Then, the normalized 173-176 Ir rate was calculated by dividing the sum of 176 Ir, 174 Ir, and 173, 175 Ir counts by the mean of Rutherford scattering events. The calculation was performed utilizing Eq. 14-16. The results are summarized in Table 20 and Figure 47.

Table 20. 173-176 Ir rate obtained on detectors with four different materials at four different positions. For some materials, the rates are zero because they could not be determined due to low statistics.

Bare Si MDDA Si+Au C11-Im Sum 𝑅,

•10 -5

𝛿𝑅,

•10 -5 𝑅 𝛿𝑅 𝑅,

•10 -5

𝛿𝑅,

•10 -5

𝑅,

•10 -5

𝛿𝑅,

•10 -5 𝑅,

•10 -4 𝛿𝑅,

•10 The 3D plot depicted in Figure 47 shows the 173-176 Ir rate as a function of the detector position in the detector chamber and the detector material. All materials were equally effective in the 173-176 Ir sorption. In the case of the MDDA detector, the 173-176 Ir rate could not be determined.

The trend for the Sum (navy blue curve) is similar to that for 152,153 Er and 199-201 At.

However, the slope is different, and a more rapid decrease in the 173-176 Ir rate is observed at position 4. The comparison of the sum curves is discussed in Section 3.4.1.5.

Results demonstrated that changing the detector position and material changes the sorption of nuclides under this study. In addition, the highest rate was observed at position 1 regardless of the material. where 𝑦 0 is the offset, 𝐴 is the initial value, 𝜆 = -𝑅 𝑜 is the rate constant parameter, i.e. the slope of a curve.

In the present study, 𝜆 is characteristic of the chemical behavior of elements in the sRTC.

The 𝜆 values for 152,153 Er, 199-201 At, and 173-176 Ir are 0.72±0.05, 0.55±0.07, and 0.84±0.22, respectively. The comparison of the 𝜆 values summarized in Table 21 and the corresponding curves in Figure 48 confirmed that Ir and Er are non-volatile elements, whereas At is a volatile element. When the retention time of a nuclide is longer than its half-life, it gets sorbed mostly on the detector in the first position and decays almost immediately. As a result, a more steep slope of a curve and, respectively, a higher 𝜆 value are observed. This describes the non-volatile behavior of Ir and Er. Oppositely, when the retention time of a nuclide is shorter than its half-life, it moves further in the detector chamber up to the fourth position before it decays. As a result, a more gentle slope of a curve and, respectively, a smaller 𝜆 value is observed. This describes the volatile behavior of At. The count rate of 152, 153 Er (red squares), 199-201 At (blue squares), and 173-176 Ir (purple squares) as a function of the detector position. The data were fitted using Eq. 22, the offset was set to zero. Shades represent 95% confidence bands.

The results suggest there are two possible processes: ions of interest can be sorbed on the surface of the detector, or they can decay in flight. Figure 49 shows the sum of the count rates collected on four detectors at each configuration for 152, 153 Er (red squares), 199-201 At (blue squares), and 173-176 Ir (purple squares). The 152,153 Er rate obtained in configuration B is an outlier and was not included in Figure 49. The data were fitted using the linear function with the slope set to zero to find the average of the count rates for 152, 153 Er (red curve), 199-201 At (blue curve), and 173-176 Ir (purple curve) collected at each configuration.

Figure 49.

The count rate of 152, 153 Er (red squares), 199-201 At (blue squares), and 173-176 Ir (purple squares) as a function of the detector configuration. The data were fitted using the linear function with the slope set to zero. Shades represent 95% confidence bands. 152, 153 Er rate at configuration B is an outlier and was not included in calculations.

The results indicate that the total activity was constant regardless of the configuration.

Therefore, if one detector has a higher rate than another detector within one configuration, it means that the variations are due to the interactions with the detector surface.

The sum of the count rates collected on each detector at four positions for three nuclides as a function of the detector material is depicted in The count rate of 152, 153 Er (red squares), 199-201 At (blue squares), and 173-176 Ir (purple squares) as a function of the detector material. Due to low statistics, 173-176 Ir count rate on the MDDA detector could not be determined.

Detector resolution study

It was important to study whether the coating of a detector with gold, the SAMs deposition, and the detector usage during online cyclotron-based experiments influence the detector resolution. Alpha spectroscopy was used to collect alpha spectra of a four-peak alpha source on a silicon detector before and after it was coated with gold, as well as after it was functionalized with Im-C11-SH SAMs and used during the online cyclotron-based experiment. The corresponding spectra are presented in Figure 51. The FWHM and the 𝑅 𝑠 values did not increase drastically after the coating of the detector with gold, its subsequent functionalization with C11-Im SAMs, and its usage in the online experiment. These results suggest that functionalized gold-coated silicon detectors can produce well-resolved peaks of radionuclides that are alpha emitters. Additionally, they can be reused in the next online experiments having relatively the same resolution.

Conclusion

Promising results were obtained during the production of 152,153 Er, 199-201 At, and 173-176 Ir which demonstrated that changing the detector position and material changes the nuclide sorption.

The highest 152,153 Er rate was observed on the gold-coated silicon detector and the bare silicon detectors. The highest 199,200,201 At rate was observed on the gold-coated detector, while others produced equal efficiency. For 173-176 Ir all materials produced equal efficiency. The chemical behavior study of online-produced 152,153 Er, 199-201 At, and 173-176 Ir confirmed the non-volatile character of Er and Ir and the volatile character of At. It also revealed that detectors in the first position collected the plurality of the product. Alpha spectroscopy demonstrated that the functionalization of the detector surface as well as its usage during online cyclotron-based experiments do not result in the worse resolution of the detector, making it possible to reuse them.

In the second part of this dissertation, two cyclotron-based experiments were performed to test the newly developed detector setup. The results of the second experiment were described in detail in this dissertation. The sRTC was designed and used for the first time to study the chemistry of the online-produced elements, such as Ir, Er, and At. The sRTC window could maintain the pressure difference of around 350 Torr. Due to several technical issues, the count rate for Ir was significantly lower than that for Er and At. The efficiency of the thiolate-functionalized surfaces in the element adsorption was found to be comparable to that of the bare Si and the gold-coated Si detectors. Promising results were obtained during the chemical study of 152,153 Er, 199-201 At, and 173- 176 Ir demonstrating the role of the detector position and its coating on the nuclide sorption. An exponential decrease of the count rate as a function of the detector position was observed for the named nuclides. The distinct distribution of the volatile and the non-volatile elements within the detector setup was obtained. The resolution of the detectors remained in the same range after the SAMs deposition as well as after their application during online cyclotron-based experiments. This allows using the named detectors multiple times in the future.

Overall, the designed detector system can be potentially applied in the future to study the adsorption properties of online-produced superheavy elements and compare them to those of their lighter homologs.

CHAPTER V FUTURE WORK

Despite the promising results obtained during the first attempt to use the thiolatefunctionalized gold-coated silicon detectors in cyclotron-based experiments, several improvements can be implemented Secondly, the size of the sRTC funnel can be decreased which will narrow the distribution of the produced ions of interest and increase the probability of their detection on the detectors located at the end of the detector chamber. Thirdly, the chemistry studies inside the sRTC were conducted under ambient temperature. In the future, the effect of other temperatures or the temperature gradient within the detector setup could be studied. The consumption of He gas which was 500-1800 standard cubic centimeters per minute can be decreased. The better design of the sRTC box can eliminate the leakage of He gas throughout an experiment. Finally, the search for potential molecules (for example, thiols based on crown ethers) which will selectively bind one element over another can be performed.

The following student in our group will study the sorption of polonium on funtionalized gold-coated silicon detectors in the gas phase. The choice of the element was dictated by its high alpha branching ratio. The student is going to functionalize the surfaces with dithiol molecules that are potentially effective in sorbing polonium.

APPENDIX

The results of the XPS analysis are described in Section 3.

  recouvertes d'or avec des SAMs Im-C11-SH et MDDA, ainsi que la sorption de Ir(IV) et Rh(III) de solutions d'acide chlorhydrique sur des SAMs Im-C11-SH ont été étudiées. Les résultats de cette étude ont été importants pour la conception de nouveaux détecteurs en silicium recouverts d'or fonctionnalisé. Dans la deuxième partie de cette thèse, les détecteurs cités ont été utilisés lors d'expériences online au cyclotron visant à étudier la sorption de l'iridium, de l'erbium et de l'astate sur des détecteurs en silicium non fonctionnalisés et fonctionnalisés. Les résultats de cette étude pourront éventuellement être utilisés pour développer un système chimique adapté à la caractérisation chimique du Mt dans le futur. -C11-SH et MDAA SAMs sur les surfaces recouvertes d'or Les techniques de caractérisation de surface utilisées pour mesurer la rugosité, la couverture de surface, l'état chimique des SAMs, la cinétique de dégradation des SAMs, l'épaisseur des SAMs et de la saturation de surface ont décrites. Les détails techniques sont fournis dans le Chapitre 2.3.3 ConclusionDans ce travail, la caractérisation de la surface de puces de silicium recouvertes d'et d'acide 12-mercaptodécanoïque a été réalisée (Figure2). Pour les SAMs Im-C11-SH, l'AFM a révélé que le dépôt des SAMs, ainsi que le traitement liquide-UVPO, n'affectent pas la morphologie et la topologie de la surface. Les valeurs de rugosité de surface restent de l'ordre de 1,20-1,25 nm. Les NP-SIM ont montré que la plus grande couverture de surface de (99 ± 6) % a été atteinte lorsque le dépôt de SAMs a été effectué à partir d'une solution 5mM Im-C11-SH. Le nettoyage préalable des puces de silicium recouvertes d'or à l'aide du traitement liquide-UVPO a permis d'utiliser des surfaces exemptes de nombreux contaminants. L'étude de stabilité par la technique XPS des SAMs d'Im-C11-SH et de MDDA dans des conditions ambiantes de laboratoire a indiqué que les puces recouvertes d'or fonctionnalisées restent stables pendant au moins un mois après leur stockage dans des plateaux de support de plaquettes fermés, enveloppés de papier d'aluminium. Il est donc possible d'utiliser les SAMs d'Im-C11-SH et de MDDA pour la fonctionnalisation de détecteurs en silicium recouverts d'or utilisés lors d'expériences online au cyclotron. De plus, le traitement UVPO liquide s'est avéré être une technique efficace pour régénérer les surfaces en or recouvertes de SAMs Im-C11-SH. Enfin, les résultats de l'ellipsométrie ont prouvé la présence d'une monocouche de thiolate unique d'une épaisseur de

Figure 2 .

 2 Figure 2. Représentation schématique du système étudié.

Figure 3

 3 Figure 3 La saturation de surface des SAMs Im-C11-SH avec Ir (IV) en fonction de la concentration initiale d'Ir (IV) dans des solutions de HCl 0,55 M.

Figure 4 Figure 5 .

 45 Figure 4 (a) The sRTC installed on the AGGIE separator. (b) The detectors are installed inside the sRTC.

  première partie de cette thèse, la caractérisation des SAMs Im-C11-SH et MDDA sur des substrats recouverts d'or a été réalisée en utilisant différentes techniques de science des surfaces. La morphologie et la topologie de la surface des substrats d'or fonctionnalisés n'ont pas été affectées par le dépôt de SAMs d'Im-C11-SH et le traitement liquide-UVPO utilisé pour pré-nettoyer les substrats ou enlever les SAMs. Cette découverte faite avec l'AFM permet de réutiliser plusieurs fois les substrats recouverts d'or sans en altérer les propriétés. L'optimisation de la procédure de dépôt des SAMs a révélé que la plus grande couverture de surface de (99 ± 6)% peut être atteinte lorsque des solutions éthanoliques de thiol 5mM sont utilisées pour préparer les SAMs de thiolate sur l'or. Les SAMs d'Im-C11-SH et de MDDA se sont révélées stables pendant au moins un mois après leur stockage dans des plateaux de support de plaquettes fermés, enveloppés de papier d'aluminium. Ce résultat important a permis d'utiliser les SAMs d'Im-C11-SH et de MDDA pour la fonctionnalisation de détecteurs en silicium recouverts d'or utilisés lors d'expériences cyclotron online qui peuvent durer jusqu'à un mois. L'épaisseur obtenue des SAMs Im-C11-SH a prouvé la présence d'une monocouche de thiolate sur la surface de l'or. Les résultats positifs ont été obtenus lors des études de sorption de Ir(IV) et Rh(III) à partir de solutions d'acide chlorhydrique. La couverture des SAMs Im-C11-SH avec Rh(III) a été mesurée à (81.3 ± 3.8)% en utilisant NP-SIMS. Les résultats INAA ont permis de conclure que Ir(IV) peut être adsorbé sur les SAMs Im-C11-SH et MDDA avec la saturation de surface de (77 ± 12)% et (84 ± 16)%, respectivement. Sachant que les puces recouvertes d'or fonctionnalisées sont sensibles à la sorption de Ir(IV) et Rh(III), nous pouvons supposer que les SAMs nommées déposées sur des détecteurs en silicium recouverts d'or seraient efficaces pour fixer les éléments produits online dans la phase gazeuse pendant les expériences basées sur le cyclotron.Dans la deuxième partie de cette thèse, deux expériences basées sur le cyclotron ont été réalisées pour tester la nouvelle configuration du détecteur. Les résultats de la deuxième expérience ont été décrits en détail dans cette dissertation.

1 1. 1

 11 Mots-clés: Silice fonctionnalisée, Monocouches auto-assemblées d'organothiols, Sorption de l'iridium et le rhodium, Expériences on-line au cyclotronRésumé en anglaisIn this work, thiolate-functionalized gold-coated silicon detectors were proposed as new materials for the comparison of the sorption properties of superheavy elements and their lighter homologs produced during online cyclotron-based experiments. The first part of the dissertation discusses the functionalization of gold-coated silicon substrates with 1-(11-mercaptoundecyl)imidazole and 12-mercaptododecanoic acid self-assembled monolayers. The functionalized surfaces were characterized offline utilizing several surface science techniques. The successful results showed the studied materials are stable for at least one month and demonstrate the surface saturation with Ir(IV) and Rh(III) adsorbed from hydrochloric acid solutions. The second part of the dissertation discusses the new detector setup developed to study the sorption of online-produced Ir, Er, and At. The promising results demonstrated the role of the detector position and its coating on the element sorption.ivDEDICATION To my big family in Ukraine and outside of it v ACKNOWLEDGEMENTS I would like to thank a lot of people who helped me throughout my Ph.D. program. First of all, Dr. Maria Boltoeva who took me originally as a Master student and believed in me to obtain a Ph.D. degree. Thank you for offering a great opportunity to work in the well-known Heavy Elements group in one of the best universities in the United States. It was a hard decision to make, but now, I can say for sure that it was worth it. Thank you for always keeping in touch with me despite the time difference, loads of work, and family duties. Having three kids and a lot of work to do, you are the only person who would genuinely give me a helping hand without making me feel uncomfortable for asking. Prof. Charles M. Folden III, thank you for agreeing to take me as a Research Assistant to work on my Ph.D. project in collaboration with Dr. Maria Boltoeva to achieve my goal of obtaining a higher degree. Thank you for allowing me to work on such an interesting project that taught me a lot of new things I did not know before and never thought possible. Thank you for sending me to conferences where I could present my work and discuss it with others in the field. This greatly helped me with my professional development and communication skills. Thank you for always proofreading the documents I needed to submit and giving your comments. Dr. Evgeny E. Tereshatov, thank you for guiding me on how to perform the experiments I conducted during the past three years, helping me analyze my data whenever I needed it, teaching me new methods of data analysis in Origin, and putting a lot of your effort into the design of the sRTC. Thank you for showing me around the town in the country I had never been to and introducing me to the best restaurants in town. I'll never forget the first time I tried an American burger with you! vi Kevin Glennon, thank you for showing me around our lab when I came to the group. You helped me perform several experiments, always proofread documents I asked you to check for me, and have always been a nice person to talk to. Jenna Garcia, thank for you helping me with alpha spectroscopy measurements. I am impressed by how you can become engaged in someone else's work with great care. I am solemnly thankful for our friendship; you became a close friend to me. Katie Childers, I will be forever thankful for teaching me how to analyze data from online experiments in ROOT that looked unreal to me at first. Thank you for answering my questions about the separator and for working together in the cave. I was able to describe the online experiments without hesitation in this dissertation. Jenna and I miss our lunches together. Jordan Mildon, thank you for helping us to set up the separator, doing important magnet tests, and helping me with the data analysis in ROOT. It led us to perform the experiment results of which I am presenting in this dissertation. I would like to mention other members of our group who maintain a friendly environment at work: Isaac Haynes, Amelia Kirkland, and Sarah Loftin. I am grateful to my friends from Ukraine who keep in touch even though I am so far away. Thank you to all my new friends I have made in College Station who give me great company. Thank you to my boyfriend, Dustin Scriven, you fill me with a tremendous amount of support. Finally, I do not have enough words to describe how thankful I am to my family for always being supportive of me and especially to my mom Ludmila who supported the idea of studying in France which led me eventually to move to the United States where I feel safe right now. Thank you to my brother Sasha, my sister-in-law Margarita, my grandparents Fedia and Anastasia, aunt Sveta, and cousin Maxim for being there for me and cheering me up whenever I felt down. I would not be where I am right now without my family. vii CONTRIBUTORS AND FUNDING SOURCES This work was supervised by the director of the dissertation, Dr. Maria Boltoeva, CNRS Researcher at the Institut Pluridisciplinaire Hubert Curien (IPHC, UMR 7178), as well as supervisors from Texas A&M University, Prof. Charles M. Folden III of the Department of Chemistry and Dr. Evgeny E. Tereshatov of the Cyclotron Institute. The AFM measurements described in Section 3.1.1 were conducted with the help of Dr. Wilson Serem at the Texas A&M University Materials Characterization Core Facility (RRID:SCR_022202). The NP-SIMS measurements discussed in Sections 3.1.2 and 3.2.1 were acquired by Dr. Stanislav V. Verkhoturov and Dr. Dmitriy S. Verkhoturov at the Department of Chemistry, Texas A&M University. The XPS measurements depicted in Section 3.1.3 were performed by Dr. Jing Wu at the Texas A&M University Materials Characterization Core Facility (RRID:SCR_022202). The INAA measurements described in Section 3.2.2 were conducted by Dr. Bryan E. Tomlin at TEES Nuclear Science Center 1 MW TRIGA reactor. The ellipsometry measurements illustrated in Section 3.1.4 were performed by the student independently at the Department of Biomedical Engineering, Texas A&M University which gave access to the ellipsometer and the software to analyze the data. All samples for the above-mentioned analyses were prepared by the student independently. The data analysis was done with the help of the scientists mentioned above. The online cyclotron-based experiments were performed by the student and other members of the Heavy Elements Group under the supervision of Prof. Charles M. Folden III: Dr. Evgeny Tereshatov, Dr. Katherine Childers, Jenna R. Garcia, Jordan A. Mildon, Isaac W. Haynes, Sarah M. Loftin, Amelia S. Kirkland. Data analysis was done by the student with the help of Prof. Charles M. Folden III, Dr. Evgeny Tereshatov, Dr. Katherine Childers and Jordan A. Mildon. viii At the beginning of the PhD program, several experiments were conducted to finish the Master's project and were published in December 2021. A paper based on the offline experiments of this dissertation is under review by coauthors. The results of the online experiments will be discussed in an additional paper that is currently being written. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Award No. DE-FG02-93ER40773. INTRODUCTION .............................................................................................. Superheavy Elements (SHEs) ............................................................................................... 1 1.1.1 Meitnerium .................................................................................................................... 5 1.1.2 SHE Chemical Experiments ........................................................................................ 10 1.2 Iridium and Rhodium Chemistry ........................................................................................ 15 1.3 Self-Assembled Monolayers (SAMs) ................................................................................. 19 1.4 Review of Past Studies ....................................................................................................... 22 1.5 Scope ................................................................................................................................... 24 CHAPTER II EXPERIMENTS .............................................................................................. 25

Figure 2 .

 2 Figure 2. Schematics of cold-and hot-fusion reaction mechanisms with examples of the 208 Pb( 58 Fe, n) 265 Hs and the 248 Cm( 26 Mg,4-5n) 269-270 Hs reactions, respectively. Figure used with permission from ref. [8].

Figure 3 .

 3 Figure 3. The schematic diagram of the velocity filter SHIP setup in its 1994 modified version.Reprinted from ref.[START_REF]The SHIP Setup[END_REF].

Figure 4 .

 4 Figure 4. Temperature profile (left image) and integral chromatogram (right image) obtained during thermochromatography. Illustration used with permission from ref. [37].

Figure 5 .

 5 Figure 5. The experimental setup used in thermochromatography experiments performed for Cn chemistry studies at FLNR. Illustration used with permission from ref. [37].

Figure 6 .

 6 Figure 6. The experimental setup used in thermochromatography experiments performed for Nh chemistry studies at GSI. Reprinted from ref. [4].

Figure 7 .

 7 Figure 7. The speciation diagram for Rh(III) in HCl solutions with different concentration. Figure used with permission from ref. [49].

Figure 8 .

 8 Figure 8. A scheme of the alkanethiolate SAMs formation on Au[START_REF] Andreev | Cross Sections for Production of Neutron-Deficient Isotopes of At and Po in Ho+Ar, Tb+Ca, and Ta+Mg Reactions[END_REF]: physisorption (i), laying down phase formation (ii), nucleation of the standing up phase (iii), completion of the standing-up phase (iv). Illustration used with permission from ref.[START_REF] Vericat | Self-Assembled Monolayers of Thiols and Dithiols on Gold: New Challenges for a Well-Known System[END_REF].

  of 100 L of the Ir and Rh calibrator solutions were accurately transferred by pipette and heat-sealed in pre-washed 2/5-dram polyethylene irradiation vials. 500 L aliquots of initially 5.2 M Ir(IV) experimental samples and 1000 L aliquots of initially 0.52 μM, 1.0 μM Ir(IV) or 1.0 M, 1.9 M Rh(III) experimental samples in 0.55 M HCl were prepared in the same manner. The sample masses were determined with a calibrated analytical balance with a readability of 0.01 mg. The closed sample vials were weighed in an ambient atmosphere and heat-sealed before irradiation. The neutron irradiations were performed simultaneously in the in-pool facility of the Texas Engineering Experiment Station (TEES) Nuclear Science Center 1 MW TRIGA (Training,Research, Isotopes, General Atomics) reactor. The subsequent gamma-ray spectrometry was performed using a high-purity Ge (HPGe) gamma-ray detector (from ORTEC), and the data reduction was done using INAA software from Canberra Industries. Technical details for Ir(IV)

2. 3 . 1 . 2 Figure 9 .

 3129 Figure 9. Structural formulas of: (a) Im-C11-SH (highlighted are amino and imino nitrogen sites of the imidazole ring); (b) MDDA used for the preparation of the thiol solutions.

Figure 10 .

 10 Figure 10. Schematic diagram of the substrates investigated in this study. All chips were 10 mm × 10 mm.

Figure 11 .

 11 Figure 11. A scheme of the normal conducting K150 cyclotron used in this study, and the superconducting K500 cyclotron.

Figure 12 .

 12 Figure 12. Schematic of the online cyclotron-based experiment.

Figure 13 .

 13 Figure 13. From top to bottom: degrader, target, and Faraday cup ladders. Reprinted from ref. [113].

Figure 14 .

 14 Figure 14. Three telescoping arms attached to the ladders allowing the remote control over them. Reprinted from ref. [113].

Figure 15 .Figure 16 Figure 16 .

 151616 Figure 15. Electrodeposition cell used in this study to make the 141 Pr2O3 400 𝜇g/cm 2 target. (1) The main body made of polyetheretherketone (PEEK); (2) platinum anode; (3) PEEK centerpiece; (4) aluminum cathode. Figure used with permission from ref. [117].

Figure 17 .

 17 Figure 17. The AGGIE heavy element separator. Blue arrows show its main components.

Figure 18 .

 18 Figure 18. The left panel shows circular, gold-colored detectors installed inside the sRTC. The right panel shows schematic images of the sRTC including its cross-sectional view.

Figure 19 .

 19 Figure 19. Aluminized Mylar window dismounted from the sRTC.

  has four slots for silicon detectors that were purchased from AMETEK ORTEC (Oak Ridge, Tennessee, USA). The SAMs deposition procedure used during offline experiments was transferred to online сyclotron-based experiments to prepare functionalized gold-coated silicon detectors. At first, three silicon detectors were coated with 50 nm of gold after being primed with 2.5 nm of titanium by Platypus Technologies, LLC (Madison, Wisconsin, USA). The left image in Figure20shows two silicon detectors, one bare silicon and one having silicon coated with gold. Before the gold coating, the silicon detectors were masked with aluminum foil to avoid the coating of the detector housing with gold.

Figure 20 .

 20 Figure 20. Silicon and gold-coated silicon detectors (left image), "chimney" placed onto the goldcoated silicon detector (center image), and the sealed "chimney" (right image).

Figure 21 .

 21 Figure 21. The SAMs photooxidation mechanism. Reprinted with permission from R. Yan, A. Terfort, and M. Zharnikov, J. Phys. Chem. C 125, 1855 (2021). Copyright 2022 American Chemical Society.

Figure 22 .Figure 23 .

 2223 Figure 22. Alpha spectrometer used to measure the detector resolution.

Figure 23 .

 23 Figure 23. AFM images (10 × 10 μm) of (a) pure precleaned Au, (b) Im-C11-SH SAMs on precleaned Au (the first deposition), (c) Im-C11-SH SAMs on precleaned Au (the second deposition).

Figure 24 .Figure 26 .Figure 27 .Figure 28 .

 24262728 Figure 24. AFM images (2 × 2 μm) of (a) pure precleaned Au, (b) Im-C11-SH SAMs on precleaned Au (the first deposition), (c) Im-C11-SH SAMs on precleaned Au (the second deposition).

  Figure 27a,b. The intensities of the peaks at 311.2-365.2 amu and 485.2 amu decrease significantly

3. 1 . 3 Figure 29 .Figure 30 .

 132930 Figure 29. Sulfur 2p XPS for Im-C11-SH SAMs on precleaned Au; one SAMs deposition: (a) the freshly prepared SAMs; (b) SAMs removed using the liquid-UVPO treatment; (c) the freshly prepared sample stored for two weeks; (d) the freshly prepared sample stored for one month.

  contain S 2p3/2 and S 2p1/2 spin-orbit split components. Carbon XPS spectra contain the C-C, C-H component at 284.8 eV due to the presence of a hydrocarbon chain, the C-O-C component at 286 eV, and the O-C=O component at 288.5 eV as depicted in Figure 32

Figure 31 .Figure 32 .

 3132 Figure 31. Sulfur 2p XPS for MDDA SAMs on precleaned Au; one SAMs deposition: (a) the freshly prepared SAMs; (b) the freshly prepared sample stored for one week; (c) the freshly prepared sample stored for one month.

Figure 33 .

 33 Figure 33. Delta as a function of wavelength: a) full scale; b) zoomed-in region of low delta values. Measured (square symbols) and modeled (solid curves) data for bare precleaned gold (green), freshly deposited Im-C11-SH SAMs on precleaned Au (blue), Im-C11-SH SAMs on precleaned Au after one week of storage (red). The B-spline layer was used to fit the bare precleaned gold data, n=1.50. The Cauchy layer was used to fit the Im-C11-SH SAMs data, n=1.450.

3 . 2

 32 Ir(IV) and Rh(III) sorption on gold-coated chips In the following section, the results of the NP-SIMS and the INAA analyses utilized to study the sorption of Ir(IV) and Rh(III) from 0.55 M HCl solutions on non-functionalized and functionalized gold-coated chips are discussed. 3.2.1 Measurement of the coverage of non-functionalized and functionalized gold-coated chips with Ir(IV) and Rh(III) During the NP-SIMS analysis, the metal sorption from 5.2 μM Ir(IV), and 9.7 μM Rh(III) solutions in 0.55 M HCl, respectively, was performed on non-functionalized glass-coated chips and glass-coated chips functionalized with Im-C11-SH SAMs deposited from a 5 mM ethanolic thiol solution. The substrates were submerged in Ir(IV) and Rh(III) solutions for approximately 21 h.

Figure 34 .

 34 Figure 34. Mass spectra of precleaned Au functionalized with Im-C11-SH SAMs and adsorbed Rh(III) (blue line), and precleaned non-functionalized Au with adsorbed Rh(III) (black line). [Rh]init = 9.7 μM, [HCl] = 0.55 M. (a) Mass range of 200 -290 amu showing characteristic peaks of RhCl3 -, RhCl4 -and RhCl5 -clusters. (b) Mass range of 206 -216 amu showing zoomed-in ions of RhCl3 -clusters and their interference with other ions. (c) Mass range of 242 -252 amu showing zoomed-in ions of RhCl4 -clusters and their interference with other ions. (d) Mass range of 400 -480 amu showing characteristic peaks of Rh2Cl7 -and Rh3Cl4H -clusters. (e) Mass range of 580 -650 amu showing a characteristic peak of Au3S -clusters important for the calculation of the coverage of Au with Im-C11-SH SAMs.

  35 Cl3 -ion (208 amu), Ytot (Rh 35 Cl3 -), was divided by the coincidence yield of Rh 35 Cl3 -ion, Ycoinc (Rh 35 Cl3 -):

( 522 -Figure 35 .

 52235 Figure 35. Mass spectra of precleaned Au functionalized with Im-C11-SH SAMs and adsorbed Ir(IV) (orange line), and precleaned non-functionalized Au with adsorbed Ir(IV) (black line). [Ir]init = 5.2 μM, [HCl] = 0.55 M. (a) Mass range of 280-440 amu showing characteristic peaks of IrCl3 -and IrCl4 -clusters. (b) Mass range of 521.5 -571.5 amu showing characteristic peaks of Ir2Cl4 -and Ir2Cl5 -clusters. (c) Mass range of 588 -650 amu showing characteristic peaks of Ir2Cl6 - and Ir2Cl7 -clusters. (d) Mass range of 870 -950 amu showing characteristic peaks of Ir3Cl9 -and Ir3Cl10 -clusters.

3. 2 . 2

 22 Measurement of the surface saturation of non-functionalized and functionalized goldcoated chips with Ir(IV) During the INAA analysis, the initial Ir(IV) concentration was varied in the range of 0.5 -5.2 μM in 0.55 M HCl to study the surface saturation of gold-coated silicon or glass chips functionalized with Im-C11-SH SAMs deposited from a 5 mM ethanolic thiol solution, and nonfunctionalized gold-coated chips. The substrates were submerged in Ir(IV) solutions for approximately 21 h.

Figure 36 illustratesFigure 36 .

 3636 Figure 36 illustrates that the surface saturation of Im-C11-SH SAMs with Ir(IV) increases

Figure 37 .

 37 Figure 37. Gamma-ray spectra of (a) 192 Ir and (b) 104m Rh as measured with an HPGe detector showing full energy photopeaks at 316.51 keV and 51.42 keV, respectively. The insets of the spectra show the positions of the named photopeaks.

1-( 11 -

 11 mercaptoundecyl)imidazole and 12-mercaptododecanoic acid self-assembled monolayers was performed. For Im-C11-SH SAMs, AFM revealed that the SAMs deposition, as well as the liquid-UVPO treatment, do not affect the surface morphology and topology. The surface roughness values remain in the order of 1.20-1.25 nm. NP-SIMs showed that the highest surface coverage of (99 ± 6)% was reached when the SAMs deposition was performed from a 5mM Im-C11-SH solution. Precleaning of gold-coated silicon chips using the liquid-UVPO treatment allowed the use of surfaces free of numerous contaminants. The XPS stability study of Im-C11-SH and MDDA SAMs under ambient laboratory conditions indicated that the functionalized gold-coated chips remain stable within at least a month of their storage in closed wafer carrier trays, wrapped with aluminum foil. This makes it possible to use Im-C11-SH and MDDA SAMs for the functionalization of gold-coated silicon detectors utilized during online cyclotron-based experiments. Also, the liquid-UVPO treatment was found to be an effective technique to regenerate the gold surfaces covered with Im-C11-SH SAMs. Finally, ellipsometry results proved the with a thickness of 1.690 ± 0.014 nm on the surface of gold. After one week of sample storage, the thickness remained relatively the same which excludes degradation processes during this period. NP-SIMS and INAA illustrated the successful sorption of Rh(III) and Ir(IV), respectively, on precleaned functionalized gold-coated chips. The coverage of Im-C11-SH SAMs with Rh(III) was measured to be (81.3 ± 3.8)% using NP-SIMS. INAA results led to the conclusion that Ir(IV) can be adsorbed from 5.4 μM Ir(IV) solutions in 0.55 M HCl on gold-coated silicon chips functionalized with Im-C11-SH SAMs and gold-coated glass chips functionalized with MDDA SAMs with the surface saturation of (77 ± 12)% and (84 ± 16)%, respectively. The observed sensitivity of the functionalized gold-coated chips to the Rh(III) and Ir(IV) sorption allows to use the functionalized gold-coated silicon detectors during online cyclotron-based experiments.

(

  C11-Im), and gold-coated silicon functionalized with MDDA SAMs (MDAA). Four configurations: A, B, C, and D presented in Figure38were tested by cycling detectors through each position inside the detector chamber. So, each detector had the possibility to be in each position once.

Figure 38 .

 38 Figure 38. A schematic diagram of four configurations tested during the experiment. The blue arrow shows the entrance of the sRTC.

configurations at the same rotating degrader angle. 95 3000Figure 42 .

 9542 Figure 42.152,153 Er spectra (black histograms) collected on: (a) the Bare Si detector, (b) the Si+Au detector in configuration A with the rotating degrader at 55 degrees. Bin width: 20 keV. The peaks were fitted using Eq. 13.

  shows the152,153 Er rate as a function of the detector position in the detector chamber and the detector material. It represents all possible configurations 98 tested in the experiment. Overall, there were four detectors with four different materials at four different positions.

Figure 43 .Figure 44 .

 4344 Figure 43. 3D plot of the 152,153 Er rate as a function of the detector position and material. The rotating degrader was set to 55 degrees.

Figure 47 .

 47 Figure 47. 3D plot of the 173-176 Ir rate as a function of the detector position and material. All rotating degrader angles summed up.

3. 4 . 1 . 5

 415 Er, At, and Ir chemical behavior study Furthermore, the chemical behavior study of the online-produced nuclides was performed.

Figure 48 illustrates

 48 Figure 48 illustrates three curves obtained for152, 153 Er (red),199-201 At (blue), and173-176 Ir (purple)

Figure 48 .

 48 Figure[START_REF] Lesch | Some Data on the Thermodynamics of Platinum Metal Compounds[END_REF]. The count rate of152, 153 Er (red squares),199-201 At (blue squares), and173-176 Ir (purple squares) as a function of the detector position. The data were fitted using Eq. 22, the offset was set to zero. Shades represent 95% confidence bands.

Figure 50 .Figure 50 .

 5050 Figure 50.The count rate of152, 153 Er (red squares),199-201 At (blue squares), and173-176 Ir (purple squares) as a function of the detector material. Due to low statistics,173-176 Ir count rate on the MDDA detector could not be determined.

Figure A1 .Figure A2 .

 A1A2 Figure A1. Gold 4f, carbon 1s, and oxygen 1s XPS for Im-C11-SH SAMs on precleaned Au; one SAMs deposition: (a) the freshly prepared SAMs; (b) SAMs removed using the liquid-UVPO treatment; (c) the freshly prepared sample stored for two weeks; (d) the freshly prepared sample stored for one month.

alcanes thiols sur détecteurs silicium recouverts d'or pour la sorption des métaux

  Le sRTC a été conçu et utilisé pour la première fois pour étudier la chimie des éléments produits online, tels que Ir, Er et At. La fenêtre du sRTC pouvait maintenir une différence de pression d'environ 350 Torr. En raison de plusieurs problèmes techniques, le taux de comptage de Ir était nettement inférieur à celui de Er et At. L'efficacité des surfaces à fonction thiolate dans l'adsorption des éléments s'est avérée comparable à celle des détecteurs en Si nu et en Si recouvert d'or. Des résultats prometteurs ont été obtenus lors de l'étude chimique de152,153 Er,199-201 At, et173-176 Ir démontrant le rôle de la position du détecteur et de son revêtement sur la sorption du nucléide.Deuxièmement, la taille de l'entonnoir du sRTC peut être diminuée, ce qui réduira la distribution des ions d'intérêt produits et augmentera la probabilité de leur détection sur les détecteurs situés à l'extrémité de la chambre de détection. Troisièmement, les études chimiques à l'intérieur du sRTC ont été menées à température ambiante. À l'avenir, l'effet d'autres températures ou du gradient de température à l'intérieur du dispositif de détection pourrait être étudié. La consommation de gaz He, qui était de 500 à 1800 centimètres cubes standard par minute, peut être réduite. Une meilleure conception de la boîte sRTC peut éliminer les fuites de gaz He tout au long d'une expérience. Enfin, la recherche de moléculesRésuméCette thèse contribue aux développements pour les futures expériences visant l'élément 109, le meitnerium. Elle porte sur la préparation de silice fonctionnalisée et son application pour la séparation des éléments. Ces matériaux qu'imitent des détecteurs au silicium permettront de comparer la réactivité du meitnerium et de ses homologues, l'Ir et le Rh, vis-à-vis de ces surfaces lors d'expériences on-line. Pour la fonctionnalisation, nous avons employé la méthodologie basée 'acide 12-mercaptododécanoïque. Nous avons démontré que ces monocouches obtenus sont stables au moins pendant un mois et leur surface est saturée après l'absorption de l'Ir(IV) et Rh(III) à partir de solution aqueuse acide. La deuxième partie de la thèse porte sur l'étude de la sorption de l'Ir, l'erbium et l'astate sur les surfaces de matériaux préparés lors des expériences au cyclotron. Les résultats démontrent que la position du détecteur et son revêtement jouent un rôle important.

	sur	la	formation	de	monocouches	auto-assemblée	d'organothiols,	le	1-(11-
	mercaptoundécyl)imidazole et l

Une diminution exponentielle du taux de comptage en fonction de la position du détecteur a été observée pour les nucléides cités. La distribution distincte des éléments volatils et non volatils dans la configuration du détecteur a été obtenue. La résolution des détecteurs est restée dans la même gamme après le dépôt des SAMs ainsi qu'après leur application lors d'expériences online au cyclotron. Cela permet d'utiliser les détecteurs nommés plusieurs fois à l'avenir. Dans l'ensemble, le système de détection conçu peut être potentiellement appliqué à l'avenir pour étudier les propriétés d'adsorption des éléments superlourds produits online et les comparer à celles de leurs homologues plus légers. CHAPITRE V PERSPECTIVES Malgré les résultats prometteurs obtenus lors de la première tentative d'utilisation des détecteurs en silicium recouverts d'or fonctionnalisés au thiolate dans des expériences basées sur le cyclotron, plusieurs améliorations peuvent être apportées. Tout d'abord, une nouvelle source d'alimentation électrique achetée après l'expérience aurait permis d'augmenter le courant sur l'aimant Q1. À son tour, cela aurait amélioré la concentration des produits dans le sRTC, par conséquent, le taux de comptage de l'Ir produit en ligne aurait pu être augmenté. potentielles (par exemple, des thiols basés sur des éthers couronnes) qui lieront sélectivement un élément par rapport à un autre peut être effectuée. Le doctorant suivant dans notre groupe étudiera la sorption du polonium sur des détecteurs en silicium recouverts d'or fonctionnalisés en phase gazeuse. Le choix de l'élément a été dicté par son rapport de branchement alpha élevé. L'étudiant va fonctionnaliser les surfaces avec des molécules de dithiol qui sont potentiellement efficaces pour sorber le polonium.

Monocouches auto-assemblées d'

Table 1 .

 1 Experimental Procedures .................................................................................................... 29 2.3.1 Preparation and characterization ................................................................................. 29 2.3.1.1 Substrate pre-treatment ........................................................................................ 29 2.3.1.2 Preparation of Im-C11-SH and MDDA solutions ................................................ 30 2.3.1.3 Formation of Im-C11-SH and MDDA SAMs ...................................................... 31 2.3.2 Offline Experiments .................................................................................................... 33 2.3.2.1 Ir(IV) and Rh(III) sorption on gold-coated substrates ......................................... 33 2.3.3 Online Cyclotron-Based Experiments ......................................................................... 34 xiii 2.3.3.1 Reactions of interest ............................................................................................ 2.3.3.2 Target Chamber ................................................................................................... 2.3.3.3 AGGIE gas-filled separator ................................................................................. 2.3.3.4 Simple Recoil Transfer Chamber ........................................................................ 2.3.3.5 Detector Chamber ................................................................................................ 2.3.3.6 Alpha Spectrometry ............................................................................................. CHAPTER III RESULTS AND DISCUSSION ....................................................................... 3.1 Characterization of Im-C11-SH and MDAA SAMs on gold-coated chips .......................... 3.1.1 Evaluation of the roughness of non-functionalized and functionalized gold-coated silicon chips ................................................................................................................. 3.1.2 Measurement of the coverage of gold-coated silicon chips with Im-C11-SH SAMs .. 3.1.3 The study of the Im-C11-SH, MDDA SAMs chemical state and the kinetics of their degradation .......................................................................................................... 3.1.4 Measurement of the thickness of Im-C11-SH SAMs ................................................... 3.2 Ir(IV) and Rh(III) sorption on gold-coated chips ............................................................... 3.2.1 Measurement of the coverage of non-functionalized and functionalized gold-coated chips with Ir(IV) and Rh(III) ................................................................... 3.2.2 Measurement of the surface saturation of non-functionalized and functionalized gold-coated chips with Ir(IV). ..................................................................................... 3.3 Conclusion .......................................................................................................................... 3.4 Online Сyclotron-Based Experiments ................................................................................ Detector resolution study ................................................................................... 3.4.1.7 Conclusion ......................................................................................................... CHAPTER IV CONCLUSIONS ............................................................................................ CHAPTER V FUTURE WORK ............................................................................................ REFERENCES ........................................................................................................................... The Periodic Table of Elements ...................................................................................... 1 Figure 2. Schematics of cold-and hot-fusion reaction mechanisms .............................................. 3 Figure 3. The schematic diagram of the velocity filter SHIP setup ................................................ 6 Figure 4. Temperature profile and integral chromatogram obtained during thermochromatography ................................................................................................ 11 Figure 5. The experimental setup used in thermochromatography experiments performed for Cn chemistry studies at FLNR ........................................................................................... 12 Figure 6. The experimental setup used in thermochromatography experiments performed for Nh chemistry studies at GSI ............................................................................................... 14 Figure 7. The speciation diagram for Rh(III) in HCl solutions with different concentration ....... 18 Figure 8. A scheme of the alkanethiolate SAMs formation on Au(111) ...................................... 21 Schematic of the online cyclotron-based experiment .................................................. 36 Figure 13. Degrader, target, and Faraday cup ladders .................................................................. 38 The AGGIE heavy element separator.......................................................................... 43 xv Figure 18. Circular, gold-colored detectors installed inside the sRTC ......................................... 45 Figure 19. Aluminized Mylar window dismounted from the sRTC ............................................. 45Figure 20. Silicon and gold-coated silicon detectors, "chimney" placed onto the gold-coated silicon detector, and the sealed "chimney" .............................................................................. 47 Figure 21. The SAMs photooxidation mechanism ....................................................................... 49 Figure 22. Alpha spectrometer used to measure the detector resolution ...................................... 50 Figure 23. AFM images (10 × 10 μm) of pure precleaned Au and Im-C11-SH SAMs on precleaned Au ............................................................................................................... 52 Figure 24. AFM images (2 × 2 μm) of pure precleaned Au and Im-C11-SH SAMs on precleaned Au ............................................................................................................... 53 Figure 25. Mass spectrum of non-precleaned Au functionalized with Im-C11-SH SAMs. Mass range of 0-100 amu ............................................................................................. 55 ................................................................................................. 58 Figure 29. Sulfur 2p XPS for Im-C11-SH SAMs on precleaned Au ............................................. 62 Delta as a function of wavelength ............................................................................... 71 xvi Figure 34. Mass spectra of precleaned Au functionalized with Im-C11-SH SAMs and adsorbed Rh(III), and precleaned non-functionalized Au with adsorbed Rh(III) ........................ 75 HCl solutions ........................................................................ 82 Figure 37. Gamma-ray spectra of 192 Ir and 104m Rh ....................................................................... 85 Figure 38. A schematic diagram of four configurations tested during the experiment ................ 88 Figure 39. 152 Er calibration spectrum collected on the vertical Bare Si detector ......................... 90 Figure 40. 199-201 At calibration spectrum collected on the vertical Bare Si detector .................... 91 Figure 41. Sum of 173-176 Ir spectra collected on the Bare Si, the Si+Au, the C11-Im detectors in configuration D, and the Bare Si, the Si+Au detectors in configuration A .................. 92 ..................................................................................................................... 108 xvii Figure 49. The count rate of 152, 153 Er, 199-201 At, and 173-176 Ir as a function of the detector configuration .............................................................................................................. 109 Figure 50. The count rate of 152, 153 Er, 199-201 At, and 173-176 Ir as a function of the detector material ....................................................................................................................... 110 Figure 51. Alpha spectra of a four-peak alpha source collected on the Bare Si, the Si+Au, and the C11-Im detectors ........................................................................................................ 112 Mt isotopes produced through cold-and hot-fusion reactions in accelerator facilities. ... 7

	3.4.1 Radionuclide detection on non-functionalized and functionalized silicon detectors ..
	3.4.1.1 Multiple-peak Fit Analysis ..................................................................................
	3.4.1.2 152,153 Er detection on non-functionalized and functionalized silicon detectors ...
	3.4.1.3 199-201 At detection on non-functionalized and functionalized silicon detectors ...
	3.4.1.4 173-176 Ir detection on non-functionalized and functionalized silicon detectors ..
	3.4.1.5 Er, At, and Ir chemical behavior study ..............................................................
	3.4.1.6 APPENDIX .................................................................................................................................

2.1 Chemicals ............................................................................................................................ 25 2.2 Instruments and Analytical Techniques .............................................................................. 25 2.2.1 Atomic Force Microscopy ........................................................................................... 26 2.2.2 Nanoprojectile Secondary-Ion Mass Spectrometry .................................................... 26 2.2.3 X-ray Photoelectron Spectroscopy .............................................................................. 27 2.2.4 Ellipsometry ................................................................................................................ 27 2.2.5 Instrumental Neutron Activation Analysis (INAA) .................................................... 28 2.2.6 Other Instruments ........................................................................................................ 29 2.3

Table 2 .

 2 The single-bond and the triple-bond radii of 4d (Rh), 5d (Ir), and 6d (Mt) elements. ..... 9

Table 3 .

 3 Oxidation states of Ir and Rh and examples of their compounds ................................... 16

Table 4 .

 4 The speciation of Ir(IV) in HCl solutions with different pH .......................................... 17

Table 5 .

 5 Different types of SAMs adsorbed on different substrates ............................................. 20

Table 6 .

 6 Technical details of neutron irradiation and gamma-ray spectrometry of Ir(IV) and Rh(III) solutions ........................................................................................................................ 29

Table 7 .

 7 Alpha-decay information for the produced nuclides and the cross-sections of the corresponding reactions ................................................................................................ 37

Table 8 .

 8 Peak areas in the XPS spectra, and composition of Im-C11-SH SAMs .......................... 64

Table 9 .

 9 Peak areas in the XPS spectra, and composition of MDDA SAMs ............................... 69

Table 10 .

 10 Measured Ion Yields of RhCl3 -clusters used to measure the coverage of Im-C11-SH SAMs on precleaned Au ............................................................................................... 76

Table 11 .

 11 Measured Ion Yields of Ir2Cl6 -clusters used to measure the coverage of Im-C11-SH SAMs on precleaned Au ............................................................................................... 80

Table 12 .

 12 The measured concentration of Ir(IV) in 0.55 M HCl solutions before and after sorption, and comparison of the surface saturation of functionalized gold-coated chips with Ir(IV) .................................................................................................................... 83

Table 13

 13

	. The measured concentration of Ir(IV) in 0.55 M HCl solutions before and after sorption,
	and comparison of the surface saturation of non-functionalized gold-coated chips
	with Ir(IV) .................................................................................................................... 83

Table 14 .

 14 The measured concentration of Ir(IV) in 0.55 M HCl solutions before and after sorption, and comparison of the surface saturation of functionalized gold-coated glass chips with Ir(IV). ................................................................................................................... 84

Table 15 .

 15 Alpha-decay information for the studied nuclides and the determined fit parameters .[START_REF] Eller | Testing Molecular Homogeneity at the Nanoscale with Massive Cluster Secondary Ion Mass Spectrometry[END_REF]

Table 16 .

 16 Alpha-decay information for the studied nuclides and the width parameters used to perform the multiple-peak fit analysis of 152,153 Er spectra ........................................... 96

Table 17 .

 17 152,153 Er rate obtained on detectors with four different materials at four different positions ........................................................................................................................ 97

Table 18 .

 18 Alpha-decay information for the studied nuclides and the width parameters used to perform the multiple-peak fit analysis of 199-201 At spectra ......................................... 101

Table 19 .

 19 199-201 At rate obtained on detectors with four different materials at four different positions ...................................................................................................................... 101

Table 20

 20

	. 173-176 Ir rate obtained on detectors with four different materials at four different
	positions ...................................................................................................................... 105

Table 21 .

 21 Comparison of the rate constant parameters for173-176 Ir,152,153 Er, and 199-201 At ........ 107

Table 22 . Detector resolution data extracted from

 22

	1

alpha spectra of a four-peak alpha source collected on the silicon detector with different materials ........................................... 113

Table 1 .

 1 Mt isotopes produced through cold-and hot-fusion reactions in accelerator facilities.

	Isotopes	Half-life	Nuclear reaction	Facility Reference
	266 Mt	(1.7 -0.4 +0.6 ) ms	209 Bi( 58 Fe, n) 266 Mt	GSI	[24]
	266 Mt	(3.3 -1.0 +2.5 ) ms	208 Pb( 59 Co, n) 266 Mt	LBNL	[25]
	268 Mt	(42 -12 +29 ) ms	209 Bi( 64 Ni, n) 272 Rg	GSI	[27]
	270 Mt	(0.69 -0.26 +0.95 ) s	209 Bi( 70 Zn, n) 278 Nh	RIKEN	[10]
	278 Mt	(7.7 -3.5 +37 ) s	249 Bk( 48 Ca,3n) 294 Ts		[28]
	276 Mt 275 Mt	(0.68 -0.12 +0.20 ) s 243 Am( 48 Ca,3n) 288 Mc (9.7 -4.4 +46 ) ms 243 Am( 48 Ca,4n) 287 Mc	FLNR	[29] [30]
	274 Mt	(440 -170 +810 ) ms 237 Np( 48 Ca,3n) 282 Nh		[31]

Table 2 .

 2 The single-bond and the triple-bond radii of 4d (Rh), 5d (Ir), and 6d (Mt) elements.

	Bond	Species Class	Species	Distance, pm	Reference
				161.7	[33]
			RhH3
	Single	Hydrides		152	[35]
			IrH3 MtH3	154.3 162.999	[33]
			RhC -	161.52
		Carbides	IrC -	165.08
	Triple		MtC -RhN	173.22 159.80	[34]
		Nitrides	IrN	159.06
			MtN	166.59

Table 3 .

 3 Oxidation states of Ir and Rh and examples of their compounds[START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]. Table adapted with permission from ref.[START_REF] Le | A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction[END_REF]

	Metal	Oxidation state	3	Coordination number 4 5	6
	Ir	-2	Ir(NO)2PPh3
		-1		K[Ir(PF3)4] [Rh(CO)4] -	[Rh(NO)2Cl]n
		0		Ir4(CO)12		Rh4(CO)12
				Ir(CO)Cl(PPh3)2
		+1		[Rh(CO) 2 Cl] 2
	Ir
	Rh

Table 4 .

 4 The speciation of Ir(IV) in HCl solutions with different pH.

	pH	˂2	2-7	7-12	alkaline solution

  The high affinity of thiols to Au enables scientists to create well-defined organic substrates with useful chemical functionalities and properties which can be changed in advance based on the

	application [52].
	1.4	Review of Past Studies
		Kato et al. [81] reported the modification of gold disks or gold thin films deposited on
	cleaved mica with 1-(11-mercaptoundecyl)imidazole (Im-C11-SH) SAMs for the design of a new

conceptual electronic device. In a few works, mixed SAMs containing Im-C11-SH deposited on gold electrodes were characterized for the future development of biosensors or biocatalytic devices

[START_REF] Wei | Direct Wiring of Cytochrome C's Heme Unit to an Electrode: Electrochemical Studies[END_REF][START_REF] Zaitouna | Design and Characterization of a Metal Ion-Imidazole Self-Assembled Monolayer for Reversible Immobilization of Histidine-Tagged Peptides[END_REF]

. Gold-coated chips were modified with 12-mercaptododecanoic acid (MDDA) in the work of Chen et al. to develop a new label-free impedance biosensor based on a novel conductive linker

Table 6 .

 6 Technical details of neutron irradiation and gamma-ray spectrometry of Ir(IV) and Rh(III) solutions.

	Ir(IV)	Rh(III)

Cyclotron beam Rotating Degrader sRTC with four detectors installed Target improvements

  were implemented, the second experiment was performed. The beam energy was increased to 6.9 MeV/u (276 MeV). During this experiment, three fusion-evaporation reactions were performed:118 Sn( 40 Ar, 5n) 153 Er, 165 Ho( 40 Ar, 5n) 200 At, and 141 Pr( 40 Ar, 5n) 176 Ir. The

	D1	Q1	D2
	165 Ho( 40 Ar, 5n)	AGGIE Separator

Table 7 .

 7 Alpha-decay information for the produced nuclides and the cross-sections of the corresponding reactions.

		176 Ir	153 Er	200 At
	T 1/2, s	8.6 ± 0.4	37.1 ± 0.2	43 ± 1
	I, %	2.6	53	57
	𝝈, mb	1-10	~50	~10

  Sn( 40 Ar, 5n)153 Er reaction, a118 Sn 428 μg/cm 2 target (97.06% purity, purchased from Microfoils Co, Arlington, Washington, USA) on a 20 μg/cm 2 nat C backing was used. For the165 Ho( 40 Ar, 5n)200 At reaction, a 165 Ho 300 μg/cm 2 target (purchased from MicroMatter, British Columbia, Canada) on a 1.08 μm nat Al backing was used. The aluminum degrader of 6.29 μm was used for these two reactions. For the 141 Pr( 40 Ar, 5n) 176 Ir reaction, a 141 Pr2O3 400 μg/cm 2 target on

a 2 μm titanium (Ti) foil (99.6% purity, purchased from Goodfellow Corporation, Pittsburg, Pennsylvania, USA) was used. No aluminum degrader was used for this reaction. The target was made using the electrodeposition technique

  2 amu corresponds to the

	Mass	Fragment
	(amu)
	603	Au3C -
	615	Au3C2 -
	623	Au3S -
	639	Au3C4 -
	703	Au(Im-C11-S -)2
	788	Au4 -
	800	Au4C -
	813	Au4C2H -
	820	Au4S -
	985	Au5 -
	1017	Au5S -

  -28b. If there is a monolayer of thiol molecules present on the gold surface, it is harder for projectiles to bombard the gold surface deeply. Consequently, part of the projectiles' energy is lost for the SAMs fragmentation. This results in decreasing the peak intensities of Au -

	(197 amu), Au2 -(394 amu), Au3 -(591 amu), Au4 -(788 amu), Au5 -(985 amu) ions.

Table 8 .

 8 Peak areas in the XPS spectra, and composition of Im-C11-SH SAMs.

	Sample	Au 4f, CPS.eV	C 1s, CPS.eV	N 1s, CPS.eV	O 1s, CPS.eV	S 2p, CPS.eV	Au 4f, %	C 1s, %	N 1s, %	O 1s, %	S 2p, %	Desorbed SAMs, %
	Freshly deposited	1621.82	2474.20	295.92	334.40	131.24	33.39 50.93 6.09	6.88	2.70	0
	2 weeks storage	1802.662 2772.53	333.30	378.65	127.14	33.29 51.21 6.16	6.99	2.35	3
	1 month storage	1854.864 2794.45	263.08	411.92	119.05	34.08 51.34 4.83	7.57	2.19	9
	After
	SAMs	2979.337 1312.58	-	268.91	26.76	64.94 28.61	-	5.86	0.58	80
	removal

Table 9 .

 9 Peak areas in the XPS spectra, and composition of MDDA SAMs.

	Sample	Au 4f, CPSeV	C 1s, CPSeV	O 1s, CPSeV	S 2p, CPSeV	Au 4f, %	C 1s, %	O 1s, %	S 2p, %
	Freshly deposited	1206.5 1692.3 309.0	61.6	36.90 51.76 9.45	1.89
	1 week storage	1205.9 1595.8 257.2	76.3	38.46 50.90 8.20	2.43
	1 month storage	1447.2 1429.9 216.7	74.7	45.67 45.13 6.84	2.36

Table 10 .

 10 Measured Ion Yields of RhCl3 -clusters used to measure the coverage of Im-C11-SH SAMs on precleaned Au.

	Type of Au substrate	Ytot (Rh 35 Cl3 -)	Ycoinc (Rh 35 Cl3 -)	K (%)
	With SAMs	0.008055	0.009912	81.3±3.8
	There were not enough statistics to measure the coverage of non-functionalized Au with
	RhCl3 clusters.

Table 11 .

 11 Measured Ion Yields of Ir2Cl6 -clusters used to measure the coverage of Im-C11-SH SAMs on precleaned Au.

	Type of Au substrate	Ytot (Ir2Cl6 -)	Ycoinc (Ir2Cl6 -)	K (%)
	With SAMs	0.002543	0.003852	66.0±3.4
	Without SAMs	0.001932	0.004509	43±6

Table 12 .

 12 The measured concentration of Ir(IV) in 0.55 M HCl solutions before and after sorption, and comparison of the surface saturation of functionalized gold-coated chips with Ir(IV).

			Substrate
		Im-C11-SH SAMs on precleaned gold-coated chips
	CIr init (10 -8 M)	51.35±0.26 a	104.4±0.5 b	543.1±3.2 a
	CIr eq (10 -8 M)	50.93±0.26	100.2±0.5	514.3±3.1
	VIr, mL	2	3	3
	ΔNIr (10 14 molecules)	0.08±0.07	0.75±0.12	3.5±0.5
	N SAMs (10 14 molecules/cm 2 )		4.5
	[52]
	SS (%)	1.7±1.5	16.7±2.7	77±12
	a -silicon chip coated with 100 nm of gold
	b -glass chip coated with 50 nm of gold

Table 13 .

 13 The measured concentration of Ir(IV) in 0.55 M HCl solutions before and after sorption, and comparison of the surface saturation of non-functionalized gold-coated chips with Ir(IV).

			Substrate
		Precleaned gold-coated chips without SAMs
	CIr init (10 -8 M)	51.35±0.26 a	104.4±0.5 b	543.1±3.2 a
	CIr eq (10 -8 M)	50.98±0.26	102.1±0.5	540.0±3.2
	VIr, mL	2	3	3
	ΔNIr (10 14 molecules)	<1.3	0.40±0.12	<0.9
	N SAMs (10 14 molecules/cm 2 )
	[52]

  118 Sn( 40 Ar, 5n)153 Er, 165 Ho( 40 Ar, 5n)200 At, and 141 Pr( 40 Ar, 5n)176 Ir utilizing non-functionalized and functionalized silicon detectors are discussed in this chapter. Details of the performed nuclear reactions as well as technical details of the experimental setup are discussed in Section 2.3.3.

Table 15 .

 15 The values are shared for each peak within the same calibration spectrum.

		300	Bare Si
			Experimental Data
			Cumulative Fit Peak
	Counts	200
		100
		0
		3000 3500 4000 4500 5000 5500 6000
		Energy (keV)
		90

152 Er 152 Ho Figure 39. 152

  Er calibration spectrum (black histogram) collected on the vertical Bare Si detector with the rotating degrader at 80 degrees. Bin width: 20 keV. The peaks were fitted using Eq. 13.

Experimental Data Cumulative Fit Peak 176 Ir 174 Ir 173, 175 Ir 149 Tb Figure 41

  152,153 Er calibration spectrum were used to fit the173-176 Ir calibration spectrum. The assumption was made based on the fact that both Er and Ir are non-volatile elements. It was not possible to determine width parameters from the173-176 Ir calibration spectrum due to low statistics. The solid green, blue, orange, and red curves represent individual 𝛼-decay lines of the named nuclides, respectively. The solid pink curve is the cumulative fit peak which is in good agreement with the original histogram. The peak that is attributed to149 Tb (red curve) is overlapping with the cumulative fit peak, as a result, it is represented by the pink curve. Three width parameters were determined as listed in Table15.

		12
		10
	Counts	6 8
		4
		2
		0
		3000	4000	5000	6000
			Energy (keV)

. Sum of

173-176

Ir spectra collected on the Bare Si, the Si+Au, the C11-Im detectors in configuration D, and the Bare Si, the Si+Au detectors in configuration A (black histogram). All rotating degrader angles have been summed up. Bin width: 40 keV. The peaks were fitted using Eq. 13.

Table 15 .

 15 Alpha-decay information for the studied nuclides and the determined fit parameters.

	Nuclide

Table 16 .

 16 Alpha-decay information for the studied nuclides and the width parameters used to perform the multiple-peak fit analysis of152,153 Er spectra. The next step was to integrate the peaks of 152 Er and 153 Er. The obtained area of each peak was divided by the bin width (20 keV in this case) to calculate the number of counts for 152 Er and153 Er separately. Then, the normalized152,153 Er count rate was calculated by dividing the sum of152 Er and 153 Er counts by the mean of Rutherford scattering events. The general equations that were used to calculate the normalized152,153 Er,199-201 At, and173-176 Ir rates can be described as follows: 𝐶 is the number of counts of a nuclide, 𝑃 is the peak area, 𝐵 is the bin width, 𝑅 is 𝑛 is the number of isotopes of one element that were detected and used to calculate the total number of counts, 𝑅𝑆 𝑚 is the mean of Rutherford scattering events, 𝑅𝑆 𝐸 and 𝑅𝑆 𝑊 is the number of Rutherford scattering events collected on the Rutherford East and 97 West detectors, respectively, that were obtained by integrating the corresponding peaks in the Rutherford East and West spectra.To calculate the absolute error of the normalized rate, the following equations were used:

	Nuclide

Table 17 .

 17 152,153 Er rate obtained on detectors with four different materials at four different positions. Some values are zero due to low data statistics.

		Bare Si	MDDA	Si+Au	C11-Im	Sum
		𝑅,	𝛿𝑅,	𝑅,	𝛿𝑅,	𝑅,	𝛿𝑅,	𝑅,	𝛿𝑅,	𝑅,	𝛿𝑅,
		•10 -2	•10 -2	•10 -2	•10 -2	•10 -2	•10 -2	•10 -2	•10 -2	•10 -2	•10 -2
	Position 1	1.80	0.08 0.144 0.024 2.16	0.08	1.28	0.06 5.40 0.13
	Position 2	1.07	0.06	0.72	0.05	1.00	0.06	0	0	2.79 0.10
	Position 3	0	0	0.366 0.036 0.66	0.05 0.352 0.033 1.38 0.07
	Position 4 0.168 0.023 0.208 0.026 0.122 0.022 0.149 0.023 0.65 0.05

Table 18 .

 18 Alpha-decay information for the studied nuclides and the width parameters used to perform the multiple-peak fit analysis of199-201 At spectra.Similar to the152,153 Er data analysis, the peak areas of 201 At,200 At, and 199 At, obtained after the integration of the corresponding peaks, were divided by the bin width (40 keV in this case) to calculate the number of counts for 201 At,200 At, and 199 At separately. The bin width was increased due to low statistics. Then, the normalized 199-201 At rate was calculated by dividing the sum of

	Nuclide

201

At,

Table 21 .

 21 Comparison of the rate constant parameters for173-176 Ir,152,153 Er, and199-201 At.

	Nuclide	Chemistry	𝜆
	173-176 Ir 152,153 Er	Non-volatile	0.84±0.22 0.72±0.05
	199-201 At	Volatile	0.55±0.07

Table 22 .

 22 Detector resolution data extracted from alpha spectra of a four-peak alpha source collected on the silicon detector with different materials.

	Detector

Mt isotope with a half-life of (440 -170 +810 ) ms[START_REF] Oganessian | Synthesis of the Isotope 282 113 in the 237 Np+ 48 Ca Fusion Reaction[END_REF].

-d)

The total mass spectra in Figure 25b,26b were acquired for the substrate which was submerged into a 5 mM ethanolic Im-C11-SH solution, the SAMs deposition was done for the second time. This means the gold surface was regenerated before the second deposition by removing SAMs obtained during the first deposition from a 1.6 mM ethanolic Im-C11-SH solution.

The liquid-UVPO treatment was used to remove SAMs. Our results on the regeneration efficacy will be explained in the XPS Section 3.1.3.

In both cases, the spectra were obtained by normalization of the intensity of the detected fragments to the total number of impacts emitted during the SIMS experiment.

As was mentioned above, the method of event-by-event bombardment-detection allows the selection of specific impacts, in the present case those involving SAM-related molecular fragments.

In Figure 25, the mass spectra contain characteristic peaks of the following Im-C11-SH SAMs-Au fragments: hydrocarbon peaks CxHy -, CN -, S -, SH -, S2 -, C3N2H3CH -. The latter one is a product of the imidazole ring fragmentation.

In Figure 26-28, the mass spectra contain characteristic peaks of the following Im-C11-SH SAM-Au fragments: gold-sulfur clusters AunS -(229, 426, 623, 820, 1017 amu), AuSCxHy -(253, 255 amu), a deprotonated monomer (Im-C11-S -) (253.2 amu), a gold-molecule cluster ion Au(Im-C11-S -)2 (703 amu). Their observation verifies that Im-C11-SH molecules are self-assembled on the surface of gold, forming the strong Au-S bond at the metal-thiol interface [START_REF] Houssiau | TOF-SIMS Study of Alkanethiol Adsorption and Ordering on Gold[END_REF]. Similarly, the surface saturation with Ir(IV) was studied on gold-coated glass chips functionalized with MDDA SAMs deposited from a 5 mM ethanolic thiol solution. The substrates were submerged in Ir(IV) solutions with concentrations of 0.5 and 5.2 μM in 0.55 M HCl for approximately 21 h. The surface saturation was measured according to Eq. 12. The results summarized in Table 14 show that the highest surface saturation of (84 ± 16)% was measured at 5.4 μM initial Ir(IV) concentration. The surface saturation decreases with a decrease in the initial Ir(IV) concentration. The difference of approximately one order of magnitude can explain less production of 104m Rh compared to 192 Ir as well as fewer counts in the 104m Rh photopeak as shown in Figure 37. A calibration spectrum for 173-176 Ir illustrated in Figure 41 is a sum of 173-176 Ir spectra collected on the Bare Si, the Si+Au, the C11-Im detectors in configuration D, and the Bare Si, the Si+Au detectors in configuration A. In addition, for each of the named detectors, 173-176 Ir spectra collected at every rotating degrader angle were summed up to obtain a final spectrum. The summation was done to enable the fitting of the data with low statistics. The sRTC was filled with He gas under the pressure of 350 Torr. Utilizing Eq. 13, the best fit was obtained when centroids of parent nuclides were selected: 5118 keV for 176 Ir [START_REF] Singh | Nuclear Data Sheets for A = 172[END_REF], 5275 keV for 174 Ir [START_REF] Baglin | Nuclear Data Sheets for A=170[END_REF], and 5406 keV for 173,175 Ir. The energy for 173,175 Ir is presented as an average of 5418 keV and 5393 keV for 173 Ir [START_REF] Baglin | Nuclear Data Sheets for A = 169[END_REF] and 175 Ir [START_REF] Baglin | Nuclear Data Sheets for A=171[END_REF], respectively. Also, the centroid of the 153 Er granddaughter nuclide was selected: 3967 keV for 149 Tb [START_REF] Browne | Nuclear Data Sheets for A = 145[END_REF]. The 152 Er 𝛽 + -decay granddaughter nuclide, 152 Dy, at 3628 keV might also be observed, but the 𝛼-branching ratio is only 0.1% for which reason this nuclide's 3.4.1.3 199-201 At detection on non-functionalized and functionalized silicon detectors

Figure 44 shows the 199-201 At spectra as black histograms collected on the MDDA and the C11-Im detectors in configuration C with the rotating degrader at 45 degrees. At such an angle, the highest rate of 199-201 At was detected. The multiple-peak fit analysis of these spectra allowed to distinguish peaks of parent nuclides: 201 At at 6342 keV [START_REF] Xiaolong | Nuclear Data Sheets for A=197[END_REF], 200 At at 6465 keV [START_REF] Xiaolong | Nuclear Data Sheets for A = 196[END_REF], and 199 At 6643 keV [START_REF] Xiaolong | Nuclear Data Sheets for A = 195[END_REF]. The peak at 5952 keV primarily corresponds to the 199 At 𝛽 + -decay daughter nuclide, 199 Po, with the 𝛼-branching ratio of 12% [START_REF] Xiaolong | Nuclear Data Sheets for A = 195[END_REF]. The 𝛽 + -decay products of 200 At and 201 At:

200 Po at 5862 keV [START_REF] Xiaolong | Nuclear Data Sheets for A = 196[END_REF] and 201 Po at 5683 keV [START_REF] Xiaolong | Nuclear Data Sheets for A=197[END_REF] might also be observed, their 𝛼-branching ratios are 11.1% and 1.6%, respectively. The solid green, blue, orange, and red curves represent individual 𝛼-decay lines of the named nuclides, respectively. The pink curve is the cumulative peak which is in good agreement with the original histogram.

The 𝛼-decay information for the studied nuclides and the width parameters used to perform the multiple-peak fit analysis are presented in Table 18. The three width parameters were determined from the 199-201 At calibration spectrum and shared for all peaks within the analyzed spectrum. Likewise, the fit was performed for two other spectra collected on the Bare Si and the Si+Au detectors within this configuration, as well as all for spectra collected in three other configurations at the same rotating degrader angle.

The 3D plot depicted in Figure 45 shows the 199-201 At rate as a function of the detector position in the detector chamber and the detector material. The highest 199-201 At rate was observed on the Si+Au detector (pink curve). Other materials were equally effective in the 199-201 At sorption.

The trend for the Sum (navy blue curve) is similar to that for 152,153 Er, but the slope is different which is discussed in Section 3.4.1.5. The full width at half maximum (FWHM) of 148 Gd, 239,240 Pu, 241 Am, and 244 Cm peaks comprising the four-peak alpha source was measured in Genie™ 2000 Gamma Analysis Software.

Then, the resolution (𝑅 𝑠 ) of the detector was measured using the following equation:

Eq. 23

The detector resolution data and the centroids of peaks of the four-peak alpha source are summarized in Table 22.