Dissertations / Theses on the topic 'Protic and Aprotic Solvents'

The application of pervaporation to the dehydration of aprotic solvents was investigated in this study. The performance of a commercial membrane, Celfa CMC-VP-31, was evaluated for the dehydration of tetrahydrofuran (THF) and dimethylformamide (DMF). The membrane was demonstrated to successfully dehydrate THF and calculations of water and THF permeance performed. When the membrane was applied to the dehydration of DMF, delamination of the top selective layer was observed and thus the membrane was deemed unsuitable for DMF dehydration. ' Polyaniline (PAni) was identified as a suitable candidate polymer for the formation of an aprotic solvent stable hydrophilic pervaporation membrane. PAni was synthesised in the lab and preparation conditions optimised and scaled-up to produce polymer with consistent batch to batch properties, in suitable quantities, to fabricate���· membrane sheets with sufficient surface area for testing. Casting solutions comprising of 20 wt% PAni were stabilised using an amine, 4-methyl piperidine, to prevent gelation and cross-linking prior to casting. Membranes were cast on a polyester non-woven backing and phase inverted in water to produce an asymmetric membrane structure. Scanning Electron Microscopy was used to examine the structure of the membranes formed. The effects of thermal treatment on the membrane film and polymer were investigated by a number of analytical techniques in order to devise a suitable procedure for membrane stabilisation. Thermally cross-linked PAni membranes were demonstrated to be water selective and stable in THF, DMF, ethyl acetate and ethanol. Permeance correlations with temperature were constructed to describe the performance of the membrane discs tested during solvent dehydration and compared to experimental data. Transport across the membrane was reported to be solubility dominated for all of the solvent systems tested. Finally, an examination of the reproducibility of membrane performance was made and further tests performed, to better understand variations observed in membrane pervaporation performance.

Experimental data were obtained for the computation of mole fraction solubilities of three dichloronitrobenzenes in organic solvents at 25oC, and solubility ratios were obtained from this data. Abraham model equations were developed for solutes in tributyl phosphate that describe experimental values to within 0.15 log units, and correlations were made to describe solute partitioning in systems that contain either "wet" or "dry" tributyl phosphate. Abraham model correlations have also been developed for solute transfer into anhydrous diisopropyl ether, and these correlations fit in well with those for other ethers. Abraham correlations for the solvation of enthalpy have been derived from experimental and literature data for mesitylene, p-xylene, chlorobenzene, and 1,2-dichlorobenzene at 298.15 K. In addition, the enthalpy contribution of hydrogen bonding between these solutes and acidic solvents were predicted by these correlations and were in agreement with an established method. Residual plots corresponding to Abraham models developed in all of these studies were analyzed for trends in error between experimental and calculated values.

Afin de mieux comprendre et de dépasser les limites actuelles des systèmes métal-air non-aqueux, le mécanisme de réduction de l’oxygène (ORR) a été étudié en présence de cation alcalins dans divers solvants aprotiques. Sur la base de caractérisations électrochimiques sur électrode statique et d’électrodes tournantes disque-anneau, un mécanisme unique a été proposé afin de rendre compte de l’ORR en présence de cations alcalins. De plus, les différences observées d’un solvant à l’autre ont été expliquées en termes de capacité du solvant à solvater à la fois le cation alcalin en présence et l’anion superoxyde, mais aussi à sa capacité à séparer les paires d’ions. Un modèle cinétique basé sur ce mécanisme a montré un excellent accord avec les résultats expérimentaux<br>In order to better understand and overcome the current limitations of non-aqueous metal-air batteries, the oxygen reduction reaction (ORR) mechanism has been studied in presence of different alkali metal cations in several aprotic solvents. Based on electrochemical characterizations on static electrode and rotating ring-disk electrode, a unique mechanism has been proposed to account for ORR in presence of alkali metal cations. It has been further showed that the differences observed from one solvent to another could be linked to the solvent’s ability to solvate both the alkali metal cation and the superoxide anion, as well as its capability to separate ion-pairs. A kinetic model based on this mechanism has shown very good agreement with experimental results

Ionic liquids and deep eutectic solvents are areas of great interest to non-aqueous reaction systems. They can be fine-tuned for an array of properties and are often less harmful than other, organic, solvents. This research focused specifically on self-assembly in ionic liquids and deep eutectic solvents with an eye to understand self-assembly processes. Not only does this work offer industrial applications, for isolated reaction systems and batteries, it also provides an interesting insight into the possibility of non-aqueous life-forms. If compartmentalisation can occur without water, then perhaps so too can the other requirements of life. Ionic liquid nanostructure significantly affected phospholipid self-assembly with more nanostructure resulting in more curved micellar phases, rather than the lamellar phases observed in water and less structured ILs. This held true for both zwitterionic lipids and ionic surfactants, demonstrated by microscopy, small angle neutron and x-ray scattering. Phospholipids formed swellable lamellar phases in all fourteen of the deep eutectic solvents tested. Examination of lipid transition temperatures by polarising optical microscopy demonstrated that the components of the solvent could influence lipid behaviour and stability, solvents with long alkyl components acted as cosurfactants. Tethered lipid membranes and electrical impedance spectroscopy demonstrated that membranes could exist, and form, in a pure IL environment (ethanolammonium formate). This is the first time such a technique has been used to study membranes in an IL and offers unparalleled opportunities for further research. Furthermore, this technique was used to demonstrate the continued function of a membrane transporter, valinomycin, in ethanolammonium formate. Valinomycin continued to transport potassium with an extremely high selectivity over sodium. These results show that compartmentalisation, and even protein function, can continue even in the absence of water.

Thermodynamic parameters of transfer of single-ions from water to nitromethane are obtained using the Ph4AsPh4B convention suggested by Parker. Enthalpies of complexing of alkali-metal and silver cations with cryptand 222 in N,N-dimethylformamide, dimethylsulphoxide, propylene carbonate, acetonitrile and nitromethane were determined calorimetrically. The stability constants of alkali-metal and silver cryptates in nitromethane were determined by potentiometric titration. This is the first set of data ever reported for the thermodynamic parameters of complexing of metal-ions with cryptand 222 in nitromethane. Free energies and enthalpies are combined to give entropies of complexing of metal-ion cryptates in the dipolar aprotic solvents. Some enthalpy of complexing data in methanol are reviewed. A correlation is found between the enthalpy of transfer of a given cation and the difference in enthalpy of complexing of metal cation with cryptand 222 among two dipolar aprotic solvents. This correlation could provide a means of evaluating single-ion enthalpies of transfer among dipolar aprotic solvents from enthalpy of complexing data. Enthalpies and free energies of complexation of metal-ion cryptates in N,N-dimethylformamide, dimethylsulphoxide, propylene carbonate, acetonitrile and nitromethane are used with relevant data to obtain the thermodynamic parameters for transfer of metal-ion cryptates from water to these solvents, and from propylene carbonate to the other dipolar aprotic GO solvents. The results obtained show variation in DeltaG&deg;t, DeltaH&deg;t and Deltas&deg;t values for the metal-ion cryptates are predominantly found in transfers from water, with unappreciable variations in these parameters for transfer among dipolar aprotic solvents. The latter conclusion is based on a large number of experimental calorimetric data and suggests that cryptate conventions seem to be valid among dipolar aprotic solvents. The use of cryptand 222 for the extraction of alkali-metal salts from water into nitromethane is discussed. The thermodynamic parameters for extraction process in water-pure nitromethane system are obtained.

The development of selective SmI2-H2O-mediated mono-reductions of cyclic-1,3-diesters to the corresponding 3-hydroxy acids is described. The reaction proceeds with complete selectivity for cyclic-1,3-diesters over acyclic esters. Sequential one-pot conjugate reduction-ester reduction of alkylidene cyclic-1,3-diesters is also reported. Furthermore, we describe the exploitation of the unusual ketyl radical intermediates formed via single electron reduction of the ester carbonyl in unprecedented 5-exo-trig cyclisations providing access to highly substituted, stereo-defined, cyclopentanols and cyclopentanones. Also described is the use of a silicon control element to direct the stereochemical outcome of the SmI2-MeOH-mediated conjugate reduction-intramolecular aldol cyclisations of α,β-unsaturated lactones. These cyclisations generate two contiguous quaternary centres with complete diastereocontrol; the utility of the silicon-directing group as a synthetic handle for derivatisation of the cyclisation products has also been demonstrated. These cyclisations have been applied in a model approach to the anti-mitotic natural product pseudolaric acid B.

O objetivo deste trabalho é estudar a reatividade de acilação de celulose por anidridos de ácidos carboxílicos sob condições homogêneas em solventes apróticos dipolares (SAD), incluindo LiCl/N,N-dimetilacetamida (DMAC) e líquidos iônicos (LIs)/SAD. Os factores que contribuem para a reatividade foram quantificados através do estudo da dependência das constantes de velocidade e parâmetros de ativação sobre a composição do solvente. Após estabelecer que a condutividade é uma técnica experimental adequada para calcular as constantes de velocidade, foi estudada a acilação não catalisada e catalisada de celulose microcristalina, MCC. Foram empregados anidridos de ácidos carboxílicos com diferentes grupos acila (acetil a hexanoil; Nc = 2 a 6) nos seguintes sistemas de solventes: LiCl/DMAC, misturas de LI cloreto de 1-alil-3-metilimidazólio ( AlMeImCl ) e acetonitrila (MeCN), DMAC , dimetilsulfóxido (DMSO ) e sulfolano. Na celulose, a unidade anidra de glucose possui um grupo hidroxila primário e dois hidroxilas secundários. Usamos ciclohexilmetanol, CHM, e trans-1 ,2- ciclo-hexanodiol, CHD , como compostos modelo para os grupos (OH) primário e secundários, respectivamente. As razões das constantes de velocidade de acilação dos compostos modelo (CHM; Prim-OH) e (CHD; SEC-OH) foram empregados, após correção, a fim de dividir as constantes de velocidade global da reação de MCC em contribuições dos grupos (OH) presentes. Para os compostos modelo, verificou-se que k3 (Prim-OH) /k3 (Sec-OH) > 1, semelhante as reações de celulose sob condições heterogéneas; esta relação aumenta como uma função do aumento da Nc. As constantes de velocidade globais e parciais de acilação de MCC diminuim de anidrido etanóico a butanóico e, em seguida, aumentam para anidrido pentanóico e hexanóico, devido a mudanças sutis em - e compensações da entalpia e entropia de ativação. As constantes de velocidade para a acetilação de MCC, por anidrido etanóico na presença de concentrações crescentes do LI em DMAC, MeCN, DMSO e sulfolano foram calculados a partir de dados de condutividade. As constantes de velocidade de terceira ordem mostraram dependência linear sobre [LI]. Estes resultados foram explicados assumindo que o reagente é celulose ligado ao LI por ligação de hidrogénio. Isto foi confirmado pelos dados cinéticos da acetilação de CHM, espectroscopia de IV do último composto, e de celobiose nas misturas de LI/SAD e condutividade das misturas de solventes binários, na ausência e presença de MCC. A acetilação de celulose é mais rápida nas misturas de em LI com DMAC e DMSO do que com MeCN e sulfolano. Esta diferença é explicada, em parte, com base na alta viscosidade das soluções de biopolímeros em LI/sulfolano. Obteve-se mais informações sobre os efeitos do solvente molecular a prtir das propriedades microscópicas dos solventes e simulações por dinâmica molecular, DM. Os dados solvatocrômicos (polaridade empírica e basicidade) têm mostrado a importância da basicidade do solvente; solventes mais básicos formam ligações de hidrogênio mais fortes com os grupos (OH) da celulose, aumentando sua acessibilidade e, consequentemente sua reatividade. Este é o caso de DMAC e DMSO. Os resultados das simulações por DM indicaram a formação de ligações de hidrogénio, entre os grupos (OH) da unidade de glucose anidra do MCC, (Cl-) de LI, e o dipolo do DMAC e DMSO . Observamos que a acilação de celulose em LiCl/DMAC é eficientemente catalisada por imidazol, mas não pelo cloreto de tosila. Resultados de IV de FT e RMN de 1H indicaram a formação de N-acilimidazol que é o agente de acilação. As constantes globais e parciais de velocidade de acilação do MCC diminuiram de anidirido etanóico a butanóico e depois aumentou para anidrido pentanóico e hexanóico, devido a mudanças sutis em- e compensações da entalpia e entropia de ativação.<br>The objective of this work is to study the reactivity in cellulose acylation by carboxylic acid anhydrides under homogeneous conditions in dipolar aprotic solvents (DAS), including LiCl/ N,N-dimethylacetamide (DMAC) and ionic liquids (ILs)/DAS. Factors that contribute to reactivity were quantified by studying the dependence of reaction rates on temperature and solvent composition. After establishing that conductivity is an appropriate experimental technique to calculate the rate constants, we studied the kinetics of the homogeneous uncatalyzed and catalyzed acylation of microcrystalline cellulose, MCC, with carboxylic acid anhydrides with different acyl chain-length (Nc; ethanoic to hexanoic) in the following solvent systems: LiCl/DMAC; mixtures of the IL, 1-allyl-3-methylimidazolium chloride, (AlMeImCl) and acetonitrile (MeCN), DMAC, dimethyl sulfoxide (DMSO) and sulfolane. The anhydroglucose unit of cellulose carries one primary- and two secondary hydroxyl groups. We used cyclohexylmethanol, CHM, and trans-1,2-cyclohexanediol, CHD, as model compounds for the hydroxyl groups of the anhydroglucose unit of cellulose. The ratios of rate constants of acylation of primary (CHM; Prim-OH) and secondary (CHD; Sec-OH) groups were employed, after correction, in order to split the overall rate constants of the reaction of MCC into contributions from the discrete OH groups. For the model compounds, we have found that k3 (Prim-OH)/k3 (Sec-OH) > 1, akin to reactions of cellulose under heterogeneous conditions; this ratio increases as a function of increasing Nc. The overall and partial rate constants of the acylation of MCC decrease from ethanoic- to butanoic anhydride and then increase for pentanoic- and hexanoic anhydride, due to subtle changes in- and compensations of the enthalpy and entropy of activation. Rate constants for the acetylation of MCC, by ethanoic anhydride in the presence of increasing concentrations of the ionic liquid, IL, 1-allyl-3-methylimidazolium chloride in dipolar aprotic solvents, DAS, N,N-dimethylacetamide, DMAC, acetonitrile, MeCN, dimethylsulfoxide, DMSO and sulfolane, have been calculated from conductivity data. The third order rate constants showed a linear dependence on [IL]. These results have been explained by assuming that the reactant is cellulose hydrogen-bonded to the IL. This is corroborated by kinetic data of the acetylation of cyclohexyl methanol, FTIR spectroscopy of the latter compound, and cellobiose in mixtures of IL/DAS, and conductivity of the binary solvent mixtures in absence, and presence of MCC. Cellulose acetylation is faster in IL/DMAC and IL/DMSO than in IL/MeCN and IL/Sulfolane. This difference is explained, in part, based the high viscosity of the biopolymer solutions in IL-Sulfolane. Additional explanation came from microscopic solvents properties and molecular dynamics, MD simulations. The solvatochromic data (empirical polarity and basicity) have shown the importance of solvent basicity; basic solvents hydrogen-bond to the hydroxyl groups of cellulose increasing its accessibility, hence its reactivity. This is the case of DMAC and DMSO. Results of MD simulations indicated hydrogen-bond formation between the hydroxyl groups of the anhydroglucose unit of MCC, (Cl-) of the IL, and the dipole of the DMAC and DMSO. It has been observed that cellulose acylation in LiCl/DMAC is efficiently catalyzed by imidazole, but not by p-tosyl chloride. FTIR and 1H NMR have indicated the formation of N-acylimidazole which is the acylating agent. The overall and partial rate constants of the acylation of MCC decreased from ethanoic- to butanoic-anhydride and then increased for pentanoic- and hexanoic anhydride, due to subtle changes in- and compensations of the enthalpy and entropy of activation.

Les colorants à la fluorescéine sont largement utilisés dans différents brunchs de la chimie et des sciences connexes, tout d'abord en raison de leurs propriétés fluorescentes uniques. Parmi ces composés, les dérivés nitrés sont beaucoup moins explorés. Ce travail visait à divulguer les principales propriétés protolytiques et spectrales dans des solutions non aqueuses de ces colorants.Une série de nitrofluorescéines et de plusieurs dérivés aminés, 22 composés au total, a été étudiée en détention principalement par des méthodes spectroscopiques.Le comportement de ces composés diffère significativement de celui d'autres colorants à base de fluorescéine, par exemple des dérivés halogénés très populaires. Le déplacement de l'équilibre tautomère des formes neutres des colorants est déplacé vers la lactone. La particularité des colorants portant quatre groupes NO2 dans la partie xanthène de la molécule est la formation de lactones anioniques, provoquée par l'éloignement de la densité électronique de l'atome de carbone nodal. Une autre caractéristique est la facilité de rupture du cycle pyrane dans des solutions fortement alcalines.Les valeurs des colorants ont été déterminées par la méthode spectrophotométrique dans des solutions tampons dans du DMSO et dans plusieurs cas dans de l'acétonitrile contenant 4 % en masse de DMSO, à 25 oC.L'interprétation des valeurs nécessite une compréhension de l'état des équilibres tautomères. Par exemple, la différence entre les s de dissociation par étapes des colorants, dans le DMSO varie de 1,2 pour la 5'-nitrofluorescéine à 7,6 pour la 4,5-dinito-2,7-dibromofluorescéine. L'analyse des spectres d'absorption dans le visible permet d'identifier les structures moléculaires et ioniques des colorants. L'évaluation des fractions des tautomères a permis de calculer les constantes d'équilibre dites microscopiques, décrivant la dissociation des tautomères simples. Ces derniers coïncident avec ceux des composés modèles : les esters, l'éther et un analogue sulfo.Une étude spéciale a été consacrée à révéler la transmission des effets électroniques dans la molécule de fluorescéine en examinant l'influence des substituants NO2 et NH2 dans le résidu d'acide phtalique sur le 's des groupes OH dans la partie xanthène.L'introduction d'un groupe nitro dans la partie phtalique de la fluorescéine éteint l'émission. Étonnamment, les colorants avec quatre groupes NO2 dans la partie xanthènes présentent une fluorescence brillante dans le DMSO et aprotic. En conséquence, un nouvel indicateur fluorescent indépendant du pH, l'ester méthylique de la 2,4,5,7-tétranitrofluorescéine, très sensible à la capacité du solvant à former des liaisons hydrogène, est proposé. En outre, les conditions des anions à charge simple et double de la 5'-aminofluorescéine dans des solutions de nature différente sont élucidées.L'étude d'un mélange de solvants aprotiques et donneurs de liaisons hydrogène avec des composés modèles (BODIPY) nous permettra d'étudier plus en détail le mécanisme de l'effet des liaisons hydrogène sur les dérivés de la fluorescéine<br>Fluorescein dyes are widely used in different brunches of chemistry and related sciences, first of all owing to their unique fluorescent properties. Among these compounds, nitro derivatives are much less explored. This work was aimed to disclose the main protolytic and spectral properties in non-aqueous solutions of these dyes.A series of nitrofluoresceins and several amino derivatives, 22 compounds in total, was studied in detain mainly by spectroscopic methods.The behavior of these compounds differs significantly from that of other fluorescein dyes, e.g., very popular halogen derivatives. The shift of the tautomeric equilibrium of the neutral forms of the dyes is shifted toward the lactone. The peculiar feature of the dyes bearing four NO2 groups in the xanthenes portion of the molecule is formation of anionic lactones, caused by the pulling electron density away from the nodal carbon atom. Another feature is the ease of the rupture of the pyran ring in highly alkaline solutions.The values of the dyes were determined by the spectrophotometric method in buffer solutions in DMSO and in several cases in acetonitrile that contains 4 mass % DMSO, at 25 oC.Interpreting the values require an understanding of the state of tautomeric equilibria. For instance, the difference between the values of stepwise dissociation of the dyes, , in DMSO vary from 1.2 for 5'-nitrofluorescein to 7.6 to 4,5-dinito-2,7-dibromofluorescein. The analysis of the absorption spectra in the visible region allows identifying the molecular and ionic structures of the dyes. The evaluation of the fractions of the tautomers made it possible to calculate the so-called microscopic equilibrium constants, describing the dissociation of single tautomers. The last-named coincide with those of model compounds: esters, ether, and a sulfo analogue.A special study was devoted to revealing the transmittance of the electronic effects in the fluorescein molecule by examining the influence of NO2 and NH2 substituents in the phthalic acid residue on the s of the OH groups in the xanthenes part.Introduction of a nitro group in the phthalic part of fluorescein quenches the emission. Surprisingly, the dyes with four NO2 groups in the xanthenes part exhibit bright fluorescence in DMSO and aprotic solvents. As result, a new pH-independent fluorescent indicator, methyl ester of 2,4,5,7-tetranitrofluorescein, very sensitive to the ability of the solvent to hydrogen bonding, is proposed. Also, the conditions of single- and double-charged anions of 5'-aminofluorescein in solutions of different nature are elucidated.The study of a mixture of aprotic and hydrogen bond donor solvents with model compounds (BODIPY) will allow us to further study in more detail the mechanism of the effect of hydrogen bonds on fluorescein derivatives

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.17.03 – технічна електрохімія. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016. У дисертації наведено результати досліджень, які спрямовані на розроблення теоретичних основ та технологічних засад одержання каталітично активних наночастинок Pd-Au на склографітовій основі за імпульсного режиму електролізу в середовищі органічних апротонних розчинників. Встановлено вплив умов електролізу в середовищі апротонних розчинників на вміст компонентів та морфологію наноструктурованого осаду, геометрію і розмір частинок Pd-Au. Показана ефективність імпульсного струму під час формування наноструктурованого Pd-Au. Показана можливість одержання Pd-Au гальванічним заміщенням. З'ясовано залежність геометрії та розміру частинок Pd-Au, вмісту компонентів і морфології Pd-Au осаду, одержаного гальванічним заміщенням на поверхню маґнію, від складу DMF розчину та температури. Досліджено каталітичну активність наноструктурованих Pd-Au/GC електродів, одержаних електрохімічним методом за імпульсного режиму електролізу в DMSO розчинах, у реакції анодного окиснення метанолу. Визначена залежність каталітичної активності Pd-Au/GC від вмісту компонентів у Pd-Au осаді та концентрації метанолу в розчині. Показана висока ефективність наноструктурованого Pd-Au/GC каталізатора і можливість його використання в прямих метанольних паливних елементах.<br>Dissertation for the Degree of Candidate of Technical sciences in specialty 05.17.03 – Technical Electrochemistry. – National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. In the dissertation the results of research aimed at developing the theoretical foundations and technological foundations of obtaining catalytically active nanoparticles Pd-Au on glassy carbon basis by pulsed electrolysis in the environment of aprotic organic solvents are presented. The influence of electrolysis conditions in the environment of aprotic solvents on the content of components and morphology of nanostructured sediment, size of the particles and geometry of the Pd-Au was established. The efficiency of current pulse during the formation of nanostructured Pd-Au was shown. The possibility of obtaining Pd-Au by galvanic replacement was shown. The dependence of geometry and size of the particles of Pd-Au, content components and morphology of Pd-Au deposit obtained by galvanic replacement in the magnesium surface from the composition of the DMF solution and temperature was found out. The catalytic activity of nanostructured Pd-Au/GC electrode obtained by electrochemical method in pulse mode of electrolysis in DMSO solutions, the reaction of anodic oxidation of methanol was researched. The dependence of the catalytic activity of Pd-Au/GC content from the components in the Pd-Au deposit and the concentration of methanol in the solution was defined. The high efficiency of nanostructured Pd-Au/GC catalyst and the possibility of its use in direct methanol fuel cells was shown.

Les travaux réalisés dans le cadre de cette thèse ont porté sur la réalisation de matériaux composites nanostructurés à base de nanotubes de carbone verticalement alignés (NTC alignés) et de polymères π-conjugués en vue de leur utilisation en tant que matériaux d’électrodes dans des dispositifs de stockage d’énergie de type supercondensateurs. Dans une première partie, les travaux se sont focalisés sur la croissance par CVD d’aérosol de NTC sur des substrats d’acier inoxydable via le dépôt préalable d’une sous-couche céramique SiOx. Grâce à l’optimisation de ce procédé, des tapis de NTC longs, denses et alignés pouvant directement servir de supports à l’électrodépôt de polymères π-conjugués ont pu être obtenus. Dans une seconde partie, les travaux se sont concentrés sur l’électrodépôt de poly(3-méthylthiophène) (P3MT) en milieu liquide ionique EMITFSI sur les tapis de NTC alignés à partir d’une méthode chronopotentiométrique « séquencée » permettant de réaliser des dépôts homogènes dans la profondeur des tapis. Une composition massique optimale de 70 % de P3MT permettant d’atteindre des capacitances spécifiques de 170 F.g-1 de polymère tout en conservant des cinétiques de charge-décharges élevées, comparativement à des composites NTC/P3MT enchevêtrés, a pu être déterminée. A partir des matériaux composites optimisés, des dispositifs symétriques NTC/P3MT // P3MT/NTC et hybrides CA // P3MT/NTC ont été assemblés. Le dispositif hybride à notamment permis d’atteindre une tension de 2,7 V et une capacitance de système de 26 F.g-1 en milieu EMITFSI à 25 °C. Par ailleurs, une énergie maximale de 23 Wh.kg-1 et une puissance maximale de 6,9 kW.kg-1 ont été obtenues avec une perte de seulement 7 % après 4000 cycles. Pour finir, l’électrodépôt de polypyrrole (Ppy) a été étudié dans différents milieux liquides ioniques protiques et aprotiques. Après des études réalisées par microbalance à cristal de quartz permettant de mieux comprendre les mécanismes d’insertion des espèces ioniques lors de la croissance du polymère conjugué et lors de son dopage positif réversible, des dépôt de Ppy ont été réalisés et optimisés dans la profondeur des tapis de NTC alignés. Des nanocomposites NTC alignés/Ppy présentant des capacitances spécifiques comprises entre 100 et 130 F.g-1 ont ainsi pu être obtenus<br>This thesis focused on the elaboration of nanostructured composite materials based on vertically aligned carbon nanotubes (aligned CNT) and π-conjugated polymers and their use as electrode materials in supercapacitor-type energy storage devices. The first part focused on aligned CNT growth by aerosol-assisted CVD on stainless steel substrates and the deposition of a SiOx ceramic sublayer. Thanks to the optimization of this growth process, long, dense, and aligned CNT carpets which can directly act as support for the electrodeposition of π-conjugated polymers were obtained. The second part focused on the electrodeposition of poly (3-methylthiophene) (P3MT) in EMITFSI ionic liquid medium on aligned CNT carpets using a “pulsed” chronopotentiometric method to produce homogeneous deposits in the depth of the carpets. An optimal P3MT mass composition of 70 %, which helped achieve a specific capacitance of 170 F.g-1 of polymer while maintaining high charge-discharge kinetics, compared with NTC/P3MT entangled composites, was determined. NTC/P3MT // P3MT/NTC symmetrical devices and CA // P3MT/NTC hybrid devices were assembled using the optimized composite materials. The hybrid device reached a voltage of 2.7 V and a system capacitance of 26 F.g-1 in EMITFSI at 25 ° C. Furthermore, a maximum energy of 23 Wh.kg-1 and a maximum power of 6.9 kW.kg-1 were obtained with only a 7 % loss after 4000 cycles. Finally, the electrodeposition of polypyrrole (Ppy) was investigated in different protic and aprotic ionic liquids. After quartz crystal microbalance studies in order to better understand the insertion mechanisms of ionic species during conjugated polymer growth and during its reversible positive doping, the electrodeposition of Ppy within the deepness of the aligned CNT carpets was optimized. Aligned CNT/Ppy nanocomposites with specific capacitances ranging between 100 and 130 F.g-1 were obtained

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.17.03 – технічна електрохімія. – Національний технічний університет "Харківський політехнічний інститут", Міністерство освіти і науки України, Харків, 2019. У роботі розвинуто науковий напрям керованого електрохімічного осадження наноструктурованих осадів металів (Ag, Au, Pd) на поверхню кремнію електролізом та методом гальванічного заміщення у середовищі органічних апротонних розчинників. Встановлено, що поєднання імпульсного режиму електролізу та неводного середовища сприяє формуванню наночастинок металів. Досліджено вплив концентрації іонів відновлювальних металів на геометрію наночастинок та їх розподіл по поверхні підкладки. Вивчено залежність розмірів наночастинок металів від тривалості процесу гальванічного заміщення. Вияснено закономірності впливу температури процесу, типу поверхні кремнію, природи органічних розчинників на формування наноструктурованих осадів металів (Ag, Au, Pd) та їх морфологію. Обґрунтовано доцільність осадження наночастинок металів (Ag, Au, Pd) на поверхні кремнію, що базується на високому значенні їх стандартних електродних потенціалів й ефективності систем Si/МNPs у формуванні функціональних наноструктур і плазмонно-активних поверхонь. Експериментально встановлено такі раціональні умови електроосадження наноструктурованих металів (Ag, Au, Pd): склад електроліту, параметри імпульсного електролізу (значення катодного потенціалу, тривалість імпульсу та паузи) та тривалість процесу (кількість циклів). За Е = -1,6...-2,2 В з розчинів (0,002…0,008)М H[AuCl₄] + 0,05М Bu₄NClO₄ у DMSO; (0,001…0,006)М Pd(NO₃)₂ + 0.05M Bu₄NClO₄ у DMSO та PC; (0,025…0,1)М (NH₄)[Ag(CN)₂] у DMF, τім.:τп. = 6:300 мс, 25…800 циклів, за температури 25 °С срібло, золото та паладій осаджуються на поверхню кремнію з утворенням наночастинок та їх агломератів. Досліджено залежність геометрії наночастинок металів (Ag, Au, Pd) і морфології осадів від умов електроосадження (значення катодного потенціалу, концентрації іонів металів і тривалості процесу). Встановлено, що зі збільшенням значень цих величин спостерігається тенденція до формування осадів від дискретних частинок (від 30 нм до 70 нм) до агломератів (від 120 нм до 200 нм) і нанопоруватих плівок. Запропоновано умови контрольованого осадження наночастинок металів на кремнієву поверхню за їх геометрією. Показано, що у межах катодних потенціалів -0,2…-2,5 В із розчинів відновлювальних іонів широкого діапазону концентрацій срібло, золото та паладій осаджуються на поверхню кремнію у вигляді дискретних наночастинок, які рівномірно розподілені по поверхні підкладки. Отже, зважаючи на природу напівпровідникової підкладки, 3D ріст відновлюваного металу відбувається за механізмом Вольмера-Вебера. Показано, що у неводних розчинах сольватованих і комплексних іонів в широкому діапазоні концентрацій і температур на поверхні кремнію відбуваються процеси нанорозмірного гальванічного заміщення. Формування осаду здійснюється за механізмом Вольмера-Вебера з утворенням дискретних (острівкових) наночастинок на напівпровідниковій підкладці аналогічно до їх осадження електролізом. Високодонорні молекули органічного апротонного розчинника (L) за рахунок донорно-акцепторної взаємодії L:→M утворюють поверхневі комплекси з фіксованими MNPs. Останні зазнають своєрідного "блокування", ускладнюючи їх ріст. Це сприяє формуванню сфероподібних MNPs за рахунок "згладжуючого" ефекту. Встановлено, що природа іона металу, його концентрація, температура та тривалість процесу гальванічного заміщення є основними факторами впливу на розміри осаджених наночастинок і параметрами керованого формування наноструктур Si/МNPs. Нанорозмірне гальванічне заміщення срібла, паладію та золота у середовищі органічних апротонних розчинників забезпечує формування на кремнієвій поверхні наноструктурованих осадів металів без перебігу побічних процесів. Це дає змогу отримувати системи Si/МNPs з розмірами наночастинок до 100 нм з відносно невеликим діапазоном їх розмірів. Запропоновано принципову технологічну схему осадження наночастинок металів (Ag, Au, Pd) на кремній гальванічним заміщенням у середовищі органічних апротонних розчинників, що дало змогу одержати наноматеріали кремній/нанометал з функціональними властивостями. Наведено результати дослідженнь, використання електрохімічно осаджених наночастинок металів (Ag, Au, Pd) на поверхню кремнію для створення плазмонно-активних поверхонь і наноструктур кремнію. Встановлено залежність морфології останніх від геометрії нанесених наночастинок, як активаторів метал-активного хімічного травлення. Показано, що природа металу є головним фактором формування наноструктур кремнію – поруватої поверхні чи кремнієвих нанодротів (SiNWs). Тенденція до утворення останніх проявляється в міру збільшення значення стандартного електродного потенціалу металу. Тому, в результаті МАХТ системи Si/Au з наночастинками найбільш електрододатного металу ( 0 / 3 Au Au E  = 1,49 В) характерно утворення SiNWs, тоді як для системи Si/Ag ( 0 Ag / Ag E  = 0,78 В) – нанопоруватого кремнію. Це пояснюється електрохімічним механізмом травлення кремнію в контакті з фіксованими на його поверхні наночастинками металу. Швидкість процесів, що спричиняють травлення кремнію тим більша, чим більша різниця потенціалів між катодними та анодними ділянками. В такому ж напрямі локалізується травлення, що є однією з умов формування нанодротів і нанопор з великим відношенням довжина/діаметр. Встановлено, що на морфологію утворених під час метал активованого травлення наноструктур кремнію суттєво впливають розміри осаджених MNPs. Зокрема, форма пори, переважно, відтворює форму наночастинки металу- активатора. Так, нанопори, одержані МАХТ поверхні Si/AgNPs і Si/PdNPs за діаметром близькі до діаметру осаджених відповідно AgNPs і PdNPs та рівномірно розподілені по поверхні підкладки. Вияснено, що наночастинки паладію та золота є ефективними для одержання масивів нанодротів кремнію методом МАХТ. При тому SiNWs вертикально напрямлені до площини підкладки та характеризуються надвеликим відношенням довжини до діаметра. Таке зумовлено острівковою природою осадів PdNPs і AuNPs та рівномірним їх розподілом на поверхні підкладки. Нанорозмірний ефект металевих наночастинок на процес МАХТ проявляється у формуванні структур кремнію. Встановлено, що наночастинки паладію з розмірами менше ніж 50 нм сприяють утворенню цілісних нанодротів кремнію, а більші ніж 50 нм, що переважно є агломератами – наноструктур неправильної форми. Водночас AuNPs широкого діапазону розмірів золота й осади з різною морфологією сприяють утворенню нанодротів кремнію, які зберігають вертикальну орієнтацію відносно площини підкладки. Отже, високі значення ΔЕ0 систем Si/МNPs, дають змогу отримувати методом МАХТ нанопоруватий кремній (із Si/AgNPs, Si/PdNPs) і масив нанодротів (із Si/PdNPs, Si/AuNPs). Ширші можливості наночастинок паладію та золота порівняно з наночастинками срібла у формуванні наноструктур кремнію можна пояснити природою металу та нанорозмірним ефектом. Встановлено, що одержані на поверхні кремнію дендритні наночастинки золота підсилюють раманівський сигнал. Результати МАХТ і лабораторного випробування показали, що нанопоруваті структури кремнію, одержані на поверхні кремнію з осадженими наночастинками срібла та паладію, можна використовувати як чутливі елементи газових сенсорів (CO, NH3, CO2 та ін.); нанодроти, одержані на поверхні кремнію з осадженими наночастинками золота та паладію – як датчики у фотоелектроніці та як аноди літій-іонних акумуляторів; підкладки кремнію з дендритними наночастинки золота на поверхні – як маркери та сенсори у біомедицині. Комплекс отриманих експериментальних даних дав змогу модифікувати поверхню кремнію наночастинками металів для одержання наноструктур кремнію та плазмонно-активних поверхонь на їх основі. Реалізовані в роботі методи імпульсного електролізу дають можливість одержати фіксовані на поверхні підкладки наноструктуровані осади металів заданої форми та розмірів для виготовлення високочутливих сенсорів та сонячних елементів. Встановлено, що системи Si/PdNPs, Si/AuNPs ефективніші у формуванні кремнієвих наноструктур порівняно з системою Si/AgNPs. Це зумовлено відмінністю металів за значеннями стандартних електродних потенціалів. Результати науково-дослідних випробувань у “Науково-дослідному центрі комітету судових експертиз Республіки Білорусь” показали ефективність одержаних матеріалів для високочутливих сенсорів. Впроваджено результати роботи у навчальний процес кафедри хімії і технології неорганічних речовин НУ "Львівська політехніка" для підготовки студентів за спеціальністю 161 "Хімічні технології та інженерія" спеціалізація "Технічна електрохімія" в теоретичних та лабораторних заняттях з дисципліни "Електрохімія наноматеріалів".<br>Thesis for the degree of candidate of chemical sciences (PhD) in speciality 05.17.03 – Technical Electrochemistry. – Lviv Polytechnic National University, Lviv. – Kharkiv Polytechnic Institute National Technical University, Ministry of education and science of Ukraine, Kharkiv, 2019. The scientific direction of the controlled electrochemical deposition of nanostructured metals (Ag, Au, Pd) on the silicon surface by electrolysis and the method of galvanic substitution in the medium of organic aprotic solvents is developed. It is established that the combination of the pulsed mode of electrolysis and non-aqueous medium promotes the formation of metal nanoparticles. The effect of the concentration of reducing metal ions on the geometry of the nanoparticles and their distribution on the surface of the substrate were investigated. The dependence of the size of metal nanoparticles on the duration of the process of galvanic substitution was studied. The regularities of the influence of the process temperature, the type of silicon surface, the nature of organic solvents on the formation of nanostructured metal sediments (Ag, Au, Pd) and their morphology are revealed. Herefore, the value of cathode potentials, the duration of electrodeposition and the concentration of metal ions are the main factors influencing the morphology of the metal precipitate and the geometry of its structural particles, which is crucial for the controlled formation of nanostructures based on them. The complex of experimental data allowed to modify the silicon surface with metal nanoparticles to produce silicon nanostructures and plasmonically active surfaces based on them. The methods of pulsed electrolysis implemented in the work allow to obtain nanostructured sediments of metals of a given shape and size fixed on the substrate surface for the production of highly sensitive sensors with the subsequent conversion of sunlight into electrical energy. The dependence of geometry of nanoparticles of metals (Ag, Au, Pd) and sediment morphology on electrodeposition conditions (values of cathode potential, concentration of metal ions and process duration) are investigated. It is established that with increasing values of these values there is a tendency to form sediments from discrete particles (from 30 nm to 70 nm) to agglomerates (from 120 nm to 200 nm) and nanoporous films. It is established that the nature of the metal ion, its concentration, temperature and duration of the process of galvanic substitution are the main factors influencing the size of the deposited nanoparticles and the parameters of the controlled formation of Si/MNPs nanostructures. Nanoscale galvanic substitution of silver, palladium, and gold in organic aprotic solvents ensures the formation of nanostructured metal deposits on the silicon surface without the occurrence of side processes. This makes it possible to obtain Si/MNPs systems with nanoparticle sizes up to 100 nm with a relatively small size range. A schematic technological scheme of deposition of metal nanoparticles (Ag, Au, Pd) on silicon electroplating substitution in the environment of organic aprotic solvents was proposed, which allowed to obtain silicon/nanomaterial nanomaterials with functional properties. It has been found that Si/PdNPs, Si/AuNPs systems are more effective in forming silicon nanostructures than Si/AgNPs, due to the difference in metals by the values of standard electrode potentials. The scientific direction of the controlled electrochemical deposition of nanostructured metals (Ag, Au, Pd) on the silicon surface by electrolysis and the method of galvanic substitution in the medium of organic aprotic solvents is developed. It is established that the combination of the pulsed mode of electrolysis and non-aqueous medium promotes the formation of metal nanoparticles. The effect of the concentration of reducing metal ions on the geometry of nanoparticles and their distribution on the surface of the substrate were investigated. The dependence of the size of metal nanoparticles on the duration of the process of galvanic substitution was studied. The regularities of the influence of the process temperature, the type of silicon surface, the nature of organic solvents on the formation of nanostructured metals (Ag, Au, Pd) and their morphology are revealed. The feasibility of deposition of metal nanoparticles (Ag, Au, Pd) on the silicon surface is grounded, based on the high value of their standard electrode potentials and the efficiency of Si/MNPs systems in the formation of functional nanostructures and plasmonically active surfaces. The efficiency of combining the pulsed electrolysis regime and the environment of organic aprotic solvents for the controlled deposition of MNPs of a given geometry on a semiconductor surface is proved. The rational conditions for electrodeposition of nanostructured metals (Ag, Au, Pd) were experimentally established: the composition of the electrolyte, the pulse electrolysis parameters (cathode potential value, pulse duration and pauses) and the process duration (number of cycles). For E = -1,6 ...- 2,2 V from solutions (0,002 ... 0,008)M H[AuCl₄] + 0,05M Bu₄NClO₄ in DMSO; (0,001… 0,006)M Pd(NO₃)₂ + 0,05M Bu₄NClO₄ in DMSO and PC; (0,025… 0,1)M (NH₄)[Ag(CN)₂] in DMF, τon.:τoff. = 6: 300 ms, 25… 800 cycles, at a temperature of 25 °C silver, gold and palladium are deposited on the silicon surface to form nanoparticles. The dependence of geometry of nanoparticles of metals (Ag, Au, Pd) and sediment morphology on electrodeposition conditions (values of cathode potential, concentration of metal ions and process duration) are investigated. It is established that with increasing values of these values, there is a tendency to form sediments from discrete particles (from 30 nm to 70 nm) to agglomerates (from 120 nm to 200 nm) and nanoporous films. The conditions of controlled deposition of metal nanoparticles on a silicon surface according to their geometry are proposed. It is shown that within the cathodic potentials of -0,2 ... -2,5 V, solutions of reducing ions of a wide range of concentrations of silver, gold and palladium are deposited on the silicon surface in the form of discrete nanoparticles, which are uniformly distributed over the surface of the substrate. Therefore, due to the nature of the 3D semiconductor substrate, the growth of the recovered metal occurs by the Volmer-Weber mechanism. It is shown that in non-aqueous solutions of solvated and complex ions in the wide range of concentrations and temperatures on the silicon surface processes of nanosized galvanic substitution occur. The formation of the precipitate is carried out by the Volmer-Weber mechanism with the formation of discrete (islet) nanoparticles on a semiconductor substrate similarly to their deposition by electrolysis. High-donor molecules of organic aprotic solvent (L) due to donor-acceptor interaction L:→form surface complexes with fixed MNPs. The latter undergo a kind of "blocking", complicating their growth. This contributes to the formation of spherical MNPs due to the "smoothing" effect. It is established that the nature of the metal ion, its concentration, temperature and duration of the process of galvanic substitution are the main factors influencing the size of deposited nanoparticles and the parameters of the controlled formation of Si/MNPs nanostructures. Nanoscale galvanic substitution of silver, palladium, and gold in organic aprotic solvents ensures the formation of nanostructured metal deposits on the silicon surface without the occurrence of side processes. This makes it possible to obtain Si/MNPs systems with nanoparticle sizes up to 100 nm with a relatively small size range. The results of investigations, the use of electrochemically deposited metal nanoparticles (Ag, Au, Pd) on the silicon surface to create plasmonically active surfaces and silicon nanostructures are presented. The dependence of the morphology of the latter on the geometry of the nanoparticles deposited as activators of metal-active chemical etching. Si/PdNPs, Si/AuNPs systems have been found to be more effective in the formation of silicon nanostructures than Si/AgNPs. This is due to the difference of metals in the values of standard electrode potentials. The results of the research trials at the Research Center of the Committee of Forensic Expertise of the Republic of Belarus have shown the effectiveness of the materials obtained for highly sensitive sensors. Results of work in the educational process of the Department of Chemistry and Technology of Inorganic Substances of Lviv Polytechnic National University were introduced for specialized work 161 "Chemical technologies and engineering" specialization "Technical electrochemistry" in theoretical and laboratory classes in the discipline "Electrochemistry of nanomaterials".

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.17.03 – технічна електрохімія. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016. У дисертації наведено результати досліджень, які спрямовані на розроблення теоретичних основ та технологічних засад одержання каталітично активних наночастинок Pd-Au на склографітовій основі за імпульсного режиму електролізу в середовищі органічних апротонних розчинників. Встановлено вплив умов електролізу в середовищі апротонних розчинників на вміст компонентів та морфологію наноструктурованого осаду, геометрію і розмір частинок Pd-Au. Показана ефективність імпульсного струму під час формування наноструктурованого Pd-Au. Показана можливість одержання Pd-Au гальванічним заміщенням. З'ясовано залежність геометрії та розміру частинок Pd-Au, вмісту компонентів і морфології Pd-Au осаду, одержаного гальванічним заміщенням на поверхню маґнію, від складу DMF розчину та температури. Досліджено каталітичну активність наноструктурованих Pd-Au/GC електродів, одержаних електрохімічним методом за імпульсного режиму електролізу в DMSO розчинах, у реакції анодного окиснення метанолу. Визначена залежність каталітичної активності Pd-Au/GC від вмісту компонентів у Pd-Au осаді та концентрації метанолу в розчині. Показана висока ефективність наноструктурованого Pd-Au/GC каталізатора і можливість його використання в прямих метанольних паливних елементах.<br>Dissertation for the Degree of Candidate of Technical sciences in specialty 05.17.03 – Technical Electrochemistry. – National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. In the dissertation the results of research aimed at developing the theoretical foundations and technological foundations of obtaining catalytically active nanoparticles Pd-Au on glassy carbon basis by pulsed electrolysis in the environment of aprotic organic solvents are presented. The influence of electrolysis conditions in the environment of aprotic solvents on the content of components and morphology of nanostructured sediment, size of the particles and geometry of the Pd-Au was established. The efficiency of current pulse during the formation of nanostructured Pd-Au was shown. The possibility of obtaining Pd-Au by galvanic replacement was shown. The dependence of geometry and size of the particles of Pd-Au, content components and morphology of Pd-Au deposit obtained by galvanic replacement in the magnesium surface from the composition of the DMF solution and temperature was found out. The catalytic activity of nanostructured Pd-Au/GC electrode obtained by electrochemical method in pulse mode of electrolysis in DMSO solutions, the reaction of anodic oxidation of methanol was researched. The dependence of the catalytic activity of Pd-Au/GC content from the components in the Pd-Au deposit and the concentration of methanol in the solution was defined. The high efficiency of nanostructured Pd-Au/GC catalyst and the possibility of its use in direct methanol fuel cells was shown.

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.17.03 – технічна електрохімія. – Національний технічний університет “Харківський політехнічний інститут”, Міністерство освіти і науки України, Харків, 2019. У роботі розвинуто науковий напрям керованого електрохімічного осадження наноструктурованих осадів металів (Ag, Au, Pd) на поверхню кремнію електролізом та методом гальванічного заміщення у середовищі органічних апротонних розчинників. Встановлено, що поєднання імпульсного режиму електролізу та неводного середовища сприяє формуванню наночастинок металів. Досліджено вплив концентрації іонів відновлювальних металів на геометрію наночастинок та їх розподіл по поверхні підкладки. Вивчено залежність розмірів наночастинок металів від тривалості процесу гальванічного заміщення. Вияснено закономірності впливу температури процесу, типу поверхні кремнію, природи органічних розчинників на формування наноструктурованих осадів металів (Ag, Au, Pd) та їх морфологію. Комплекс отриманих експериментальних даних дозволив модифікувати поверхню кремнію наночастинками металів для одержання наноструктур кремнію та плазмонно-активних поверхонь на їх основі. Реалізований у роботі методи імпульсного електролізу дозволяє одержати фіксовані на поверхні підкладки наноструктуровані осади металів заданої форми та розмірів для виготовлення високочутливих сенсорів з подальшим перетворенням сонячного світла в електричну енергію.<br>Thesis for the degree of candidate of chemical sciences (PhD) in speciality 05.17.03 – Technical Electrochemistry. – Lviv Polytechnic National University, Lviv. – Kharkiv Polytechnic Institute National Technical University, Ministry of education and science of Ukraine, Kharkiv, 2019. The scientific direction of the controlled electrochemical deposition of nanostructured metals (Ag, Au, Pd) on the silicon surface by electrolysis and the method of galvanic replacement in the medium of organic aprotic solvents is developed. It is established that the combination of the pulsed mode of electrolysis and non-aqueous medium promotes the formation of metal nanoparticles. The effect of the concentration of reducing metal ions on the geometry of the nanoparticles and their distribution on the surface of the substrate were investigated. The dependence of the size of metal nanoparticles on the duration of the process of galvanic replacement was studied. The regularities of the influence of the process temperature, the type of silicon surface, the nature of organic solvents on the formation of nanostructured metal sediments (Ag, Au, Pd) and their morphology are revealed. Herefore, the value of cathode potentials, the duration of electrodeposition and the concentration of metal ions are the main factors influencing the morphology of the metal precipitate and the geometry of its structural particles, which is crucial for the controlled formation of nanostructures based on them. The dependence of geometry of nanoparticles of metals (Ag, Au, Pd) and sediment morphology on electrodeposition conditions (values of cathode potential, concentration of metal ions and process duration) are investigated. It is established that with increasing values of these values there is a tendency to form sediments from discrete particles (from 30 nm to 70 nm) to agglomerates (from 120 nm to 200 nm) and nanoporous films. It is established that the nature of the metal ion, its concentration, temperature and duration of the process of galvanic replacement are the main factors influencing the size of the deposited nanoparticles and the parameters of the controlled formation of Si/MNPs nanostructures. Nanoscale galvanic replacement of silver, palladium, and gold in organic aprotic solvents ensures the formation of nanostructured metal deposits on the silicon surface without the occurrence of side processes. This makes it possible to obtain Si/MNPs systems with nanoparticle sizes up to 100 nm with a relatively small size range. A schematic technological scheme of deposition of metal nanoparticles (Ag, Au, Pd) on silicon electroplating substitution in the environment of organic aprotic solvents was proposed, which allowed to obtain silicon/nanomaterial nanomaterials with functional properties. It has been found that Si/PdNPs, Si/AuNPs systems are more effective in forming silicon nanostructures than Si/AgNPs, due to the difference in metals by the values of standard electrode potentials. The results of the research trials at the “Research Center of the Committee of Forensic Expertise of the Republic of Belarus” proved the effectiveness of the materials obtained for the highly sensitive sensors. The results of work in the educational process of the Department of Chemistry and Technology of Inorganic Substances of NU “Lviv Polytechnic” in teaching the disciplines on the specialty 05.17.03 – “Technical Electrochemistry” were introduced.

碩士<br>東海大學<br>化學系<br>87<br>Abstract Hydrogen-bonding, acidity, and structural variation are major factors controlling potentials and mechanisms in the reduction of seven quinones. These are investigated systematically in dimethylforamide and acetonitrile solutions by cyclic voltammetry for a series of quinones with increasing basicity, and in the presence of hydroxylic additives of increasing hydrogen-bonding power or acidity. Redox effects are demonstrated over the complete interaction range, hydrogen bonding of reduced dianions to protonation of unreduced quinones. It is found that the interactions of these systems decrease in the order MeOH＞EtOH＞n-PrOH＞n-BuOH≧i-PrOH for alcohol additives. Two well-separated reduction waves, corresponding to the formation of quinone mono- and dianion, shift positively, with no loss of reversibility. The relative height of the wave remains constant. The pKa values are less, the second wave shift more positively. When reaction change to use acid as additives, the more acid, the second wave is almost irreversible. This should be too fast to measure. Using Hammett equation to understand quinones about substituent effects, we find that seven quinones are electron-donating group. The σvalues are all negative. As a result, these quinones are interacting with a series alcohols and acids which can propose the reaction mechanism in aprotic solvent as These results should be a major reaction mechanism of the electrochemistry and are supported radical reaction mechanism.

碩士<br>淡江大學<br>化學學系<br>82<br>The major works of this research is to study the effects of dielectric constant, autoprotolysis constant, and other physical or chemical constants of mixed amphiprotic and aprotic solvents on the dissociation of derivatives of benzoic acid. The pKa values was estimated by Modified conductometric meth od. Personal computer which was connected with conductometer was used not only for recording the data in measurements but also for calculating the results of experiment. The mixtures of acetone and water in different ratio was use as mixed solvents, and the derivatives of benzoic acid was used as solutes. The pKa values of solutes in different mixed solvent and the effects of physical constants of solvents and the struc- tures of solutes was widely discussed in this paper.

碩士<br>國立清華大學<br>化學系<br>89<br>Abstract The square planar complex ion, Ni(C-rac-1,7-CTH)2+ (1,7-CTH = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacycloteradecane or tetb), theoretically can exist in 10 diasteredisomers, depending on the configurations of the four asysmmetric secondary amine center. The synthesis, characterization, x-ray structural and conformation studies of the five isomers were reported. Among these the molecular model of α-Ni(C-rac-1,7-CTH)2+ isomer indicates that the two axial sites are quite open and accessible to small monodentate ligands, as the methyl groups attached to the asymmetric carbons are all equatorial. According to Bosnich etal, the complex ionα-Ni(C-rac-1,7-CTH)2+, possesses trans-V configuration. With bidentate or even strong monodenate ligands, this isomeric form affords the cis-derivatives with the macrocyclic ligand is in folded state. Equilibrium constants and five coordinated ligand substitution kinetic studies on Cu(C-rac-1,7-CTH)2+ with monodentate ligands had been published. The study of substitution reaction in five coordinated complexes has given attention because they exist an intermediate state, in both a kinetic and steric sense, between the four coordinates complexes which are open to nucleophilic attack and the six coordinated systems which are not. In case of five coordinated complexes, both associative and dissociative mechanisms are possible by heiter added or lose of an monodentate ligands. In aprotic solvent the equilibrium constants for the reaction of Ni(TMC)2+ with halide ions reported. Here we report equilibrium constants for the reactions of α-Ni(C-rac-1,7-CTH)2+ with halide ion in aprotic solvents by kinetic and spectrophotometric methods and the x-ray crystal structure of five coordinated α-[Ni(C-rac-1,7-CTH)(Cl)](ClO4) complex.

碩士<br>國立中山大學<br>光電工程學系研究所<br>103<br>In order to obtain an anode with flexibility and high conductivity, lots of groups try to enhance the conductivity of PEDOT:PSS with adding polar solvents─such as glycol, ethanol and using post-treatment by immersing acid and solvents. These results show that, by varying the arrangement and ratio between PEDOT and PSS, those two different ways are all can enhance the conductivity more than three orders. In recent years has been measured and confirmed. In this research, we use the polar aprotic solvents to treat the PEDOT:PSS solution and film by heat treatment and doping. Through optimization of the parameters, we can effectively enhance the conductivity of PEDOT:PSS from 0.3 (S/cm) to 1200 (S/cm) and 700 (S/cm) by an easy, stable, fast and height adaptation method. Four orders of conductivity can be enhanced. The films with different treatment were investigated and compared with each other in the difference of optical conductivity, transmittance, work function, surface roughness, surface morphology, and stability. The films also use XPS and UV-vis absorption to analyze the conductivity enhancement mechanism. When the additive and heat-tratment PEDOT:PSS anode device at the luminance of 1000 cd/m2 , the performance of current efficiency are 15.3 (cd / A) and 21.2 (cd / A), power efficiency are 6.3 (lm / W) and 6.7 (lm / W) and EQE are 7.5 (%) and 9.8 (%).

Research Doctorate - Doctor of Philosophy (PhD)<br>This thesis relates the confined structure of several ionic liquids (ILs) and mixtures of ILs with various <i>n</i>-alkanols and the polymer poly(ethylene oxide) (PEO) to their nanoscale friction behaviours. The influence of various parameters including IL molecular structure, applied electric potential, bulk liquid viscosity and interfacial liquid viscosity on nanoscale friction were studied. Friction force microscopy (FFM) was used to investigate the friction behaviours of a series of protic ionic liquids (PILs) confined between a silica colloidal probe and a mica surface. The effect of solvophobic interactions on friction was investigated by varying cation alkyl chain length (propylammonium cation <i>vs.</i> ethylammonium cation). The effect of the hydrogen bonding capacity of both the cation (ethanolammonium cation <i>vs.</i> ethylammonium cation) and anion (nitrate <i>vs.</i> formate) was also studied. The effect of steric hindrance was probed using an IL (dimethylethylammonium formate) with weak interfacial structure. The friction coefficient changed at a critical normal load equal to the final push-through force in normal force-distance profiles in each IL. At this critical normal load all but a single layer of ions was removed from between the surfaces. Soft contact atomic force microscopy (AFM) imaging showed a change in the morphology of the propylammonium nitrate (PAN)-mica system from a structure with an undulating appearance to one with a worm-like appearance as the imaging load crossed the critical normal load. This indicated a structural rearrangement, consistent with the number of confined ion layers changing as load increased. Addition of <i>n</i>-alkanols to PAN resulted in a decrease in friction. The reduction was dependent on the concentration of n-alkanol, but independent of <i>n</i>-alkanol alkyl chain length. The friction reduction was not correlated with the bulk viscosity of the system, and thin-film drainage experiments showed that localised viscosity reductions did not occur in the system. The decrease in the friction force was attributed to weakening of intermolecular interactions between ions adsorbed to the mica surface and those in near surface layers. Friction was reduced when PEO was adsorbed to silica surfaces and immersed in pure PAN and in the aprotic ionic liquid (AIL) 1-butyl-3-methylimidazolium tetrafluoroborate. A range of PEO molecular weights were investigated. Theoretical fits to AFM force-distance profiles showed that PEO adsorbed onto silica from both ILs in a mushroom conformation. FFM experiments showed that friction was lower when PEO was present compared to either pure IL, and that friction decreased as polymer molecular weight increased. Friction was reduced due to the high osmotic pressures generated as polymer layers were compressed; this provided an effective barrier to direct surface-surface contact. The ability of an IL to lubricate an electrically charged contact was investigated by applying a surface potential to a gold surface lubricated by the IL 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl) trifluorophosphate. Friction varied as a function of both the sign and magnitude of the bias. The composition of the adsorbed layer of ions varied as surface polarity changed from positive to negative or vice versa. The adsorbed layer composition influenced ion packing arrangements and both had a significant effect on friction; the relatively long alkyl chains of the cations lowered friction more effectively than the bulky anions.