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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Conducting triarylamine supramolecular polymers : from electronics to plasmonics / Des polymères supramoléculaire des triarylamines : des applications électroniques aux applications plasmoniques

Armao, Joseph John 23 September 2015 (has links)
Dans ce travail, la chimie supramoléculaire est utilisé pour créer des polymères triarylamine auto-assemblées affichant l’auto-assemblage, la conduction, et les propriétés plasmoniques. Deux classes de polymères triarylamine auto‐assemblées sont décrits en détail, y compris leurs propriétés d'auto-assemblage, structure à empiler, ainsi que le comportement électrochimique. En outre, l'application de ces matériaux à l'égard des cellules solaires organiques et spintronique moléculaire est examinée. Enfin, la capacité de ces fibres pour être utilisé dans des applications plasmoniques est détaillé, dans lequel les assemblages supramoléculaires sont présentés à quelques résonances plasmoniques de nanoparticules, agissent comme guides plasmoniques, et induisent l'ordre des nanoparticules plasmoniques à une interface liquide-liquide. Ces propriétés émergentes sont intimement liés aux interactions supramoléculaires démontrant ainsi de nouvelles applications de polymères supramoléculaires. / In this work, supramolecular chemistry is used to create self-assembled triarylamine polymers displaying novel self-assembly, conduction, and plasmonic properties. Two classes of self-assembled triarylamine polymers are described in detail, including their self-assembly properties, stacking structure, as well as electrochemical behavior. Additionally, the application of these materials towards organic solar cells and molecular spintronics is examined. Finally, the ability of these fibers to be used in plasmonic applications is detailed, wherein the supramolecular assemblies are shown to couple plasmonic nanoparticle resonances, act as plasmonic waveguides, and induce the ordering of plasmonic nanoparticles at a liquid-liquid interface. These emergent properties are intimately linked to the supramolecular interactions thereby demonstrating novel applications of supramolecular polymers.
12

Controlling the Physical Properties of Organic Semiconductors through Siloxane Chemistry and other Organic Electronic Materials

Kamino, Brett Akira 10 January 2014 (has links)
Triarylamine type materials with vastly altered physical properties are synthesized by hybridizing organic semiconducting structures with silicone and siloxane groups. By altering the silicon content of these materials, we can tune their physical composition from free flowing liquids, to amorphous glasses, to cross-linked films. Much of this modification is enabled by the unique use of a metal-free Si-H activation chemistry; the Piers-Rubinsztajn reaction. This chemistry is demonstrated to be a general and rapid way to build up hybrid semiconducting structures. Key to the utility of these materials in electronic devices, it is shown that hybridization with silicon groups has a negligible effect on the useful electrochemical properties of the base materials. Building on this, it is shown that charge carrier mobility through a prototypical liquid organic semiconductor is similar to the base materials and transport is described by existing dispersive transport theories. Finally, two side projects in the area of organic electronics are discussed. New phthalonitrile based fluorophores are characterized and their utility as deep-blue emitting dopants in organic light emitting diodes is demonstrated. These same π-extended phthalonitriles can also be used as precursors to new red-shifted BsubPcs which display exceptional electrochemical stability and tuning.
13

Controlling the Physical Properties of Organic Semiconductors through Siloxane Chemistry and other Organic Electronic Materials

Kamino, Brett Akira 10 January 2014 (has links)
Triarylamine type materials with vastly altered physical properties are synthesized by hybridizing organic semiconducting structures with silicone and siloxane groups. By altering the silicon content of these materials, we can tune their physical composition from free flowing liquids, to amorphous glasses, to cross-linked films. Much of this modification is enabled by the unique use of a metal-free Si-H activation chemistry; the Piers-Rubinsztajn reaction. This chemistry is demonstrated to be a general and rapid way to build up hybrid semiconducting structures. Key to the utility of these materials in electronic devices, it is shown that hybridization with silicon groups has a negligible effect on the useful electrochemical properties of the base materials. Building on this, it is shown that charge carrier mobility through a prototypical liquid organic semiconductor is similar to the base materials and transport is described by existing dispersive transport theories. Finally, two side projects in the area of organic electronics are discussed. New phthalonitrile based fluorophores are characterized and their utility as deep-blue emitting dopants in organic light emitting diodes is demonstrated. These same π-extended phthalonitriles can also be used as precursors to new red-shifted BsubPcs which display exceptional electrochemical stability and tuning.
14

Synthesis and self-assembly of triarylamines modified with nucleobases / Synthèse et auto-assemblage de triarylamines modifiées par des nucléobases

Cao, Qing 18 January 2017 (has links)
Les triarylamines sont de petites molécules largement utilisées comme porteurs de charges dans le domaine de l'électronique organique, car elles présentent des mobilités de transport de trous élevées. En 2010, notre groupe a démontré pour la première fois que les molécules de triarylamine décorées avec des groupements amide subissent une polymérisation supramoléculaire. D'autre part, les propriétés de reconnaissance des résidus de nucléobases ont été largement utilisées au cours des 25 dernières années pour déclencher des processus d'auto-assemblage de polymères ou de petites molécules en polymères supramoléculaires bien définis. Dans cette thèse, une série de molécules triarylamine décorées avec des amides sur leurs chaînes latérales avec différentes nucléobases comme la guanine, la thymine et la cytosine ont été synthétisées. Nous avons démontré que les monomères de triarylamine conservent leurs propriétés d'auto-assemblage dans les solvants chlorés lors de l'irradiation lumineuse, à condition que le résidu de la nucléobase n'affecte pas les interactions non covalentes nécessaires pour l'auto-assemblage du cœur de triarylamine. En outre, nous avons démontré que la présence d'amines primaires sur le résidu de la nucléobase interdit la formation de structures auto-assemblées dès qu'elles ne sont pas incorporées dans des réseaux de liaisons hydrogène. Dans un deuxième chapitre, nous avons ensuite étudié les auto-assemblages de nos molécules triarylamine-nucléobase dans des solvants organiques en utilisant des ions ou de petites molécules comme matrice. Tout d'abord, la polymérisation supramoléculaire de la triarylamine-monothymine à l'aide de mélamine dans divers solvants a été étudiée. Par ailleurs, l'influence sélective des ions de mercure sur les propriétés sensibles légères de triarylamine-monothymine a été soigneusement analysé. Enfin, les polymères supramoléculaires hybrides de triarylamine-monoguanine conjugué en absence et en présence d'ions potassium ont été obtenus. En particulier, nous avons décrit le premier exemple de polymères supramoléculaires construits à partir de mélamine dans des solvants organiques. Dans l'ensemble, l'impact de ce travail est triple: a) il conduit à une meilleure compréhension du comportement d'auto-assemblage des conjugués de triarylamine, b) il influence la conception des structures de triarylamine auto-assemblées et c) il offre de nouvelles approches pour l'auto-assemblage des molécules de triarylamine. / Triarylamines are small molecules widely used as charge carriers in the field of organic electronics as they display high hole-transport mobilities. In 2010, our group demonstrated for the first time that chemically-tailored triarylamine amide molecules undergo supramolecular polymerization. On the other hand, the recognition properties of nucleobase residues have been widely used in the last 25 years to trigger self-assembling processes of polymers or small molecules into well-defined supramolecular polymers.In this thesis, a series of triarylamine amide molecules decorated on their side chains with various nucleobases such as guanine, thymine and cytosine have been synthesized. We have demonstrated that the triarylamine monomers retain their self-assembling properties in chlorinated solvent upon light irradiation, provided that the nucleobase residue does not affect the non-covalent interactions necessary for the self-assembly of the triarylamine core. In addition, we have demonstrated that the presence of primary amines on the nucleobase residue prohibit the formation of self-assembled structures, as soon as they are not embedded in hydrogen bonding arrays. In a second chapter, the templated self-assemblies of our triarylamine-nucleobase molecules in organic solvents were studied. Firstly, templated supramolecular polymerization of triarylamine-monothymine using melamine in various solvents was investigated. Besides, selective influence of mercury ion on the light responsive properties of triarylamine-monothymine was analyzed carefully. At last, hybrid supramolecular polymers of triarylamine-monoguanine conjugate in absence and in presence of potassium ion were obtained. In particular, we have described the first example of supramolecular polymers build from melamine in organic solvents. Overall, the impact of this work is three-fold: a) it leads to a better understanding of the self-assembly behavior of triarylamine conjugates, b) it influences the design of self-assembling triarylamine structures and c) it offers new approaches for the self-assembly of triarylamine molecules.
15

Light-triggered self-assemblies of triarylamine-based conjugates / Auto-assemblages photo-induits des dérivés triarylamine

Wolf, Adrian 23 January 2014 (has links)
Le but de cette thèse était d’auto-assembler des entités triarylamines donneurs d’électrons et capables de s’empiler en fibres conductrices sous l’action de la lumière, avec des entités accepteurs d’électrons de manière à obtenir des hétérojunctions supramoléculaires. Ces objectifs ont été atteints dans des versions dites statiques (distances constantes entre canauxdonneur et accepteur d’électrons) mais aussi dans une version dynamique ou la distance entre unités électroactives change grâce à l’action contrôlée d’un muscle moléculaire intégré. Ces systèmes auto-assemblés fonctionnels ont montré des changements très importants de leurs propriétés optoélectroniques en réponse à des stimuli orthogonaux comme la lumière et le pH. / The aim of this thesis was to self-assemble electron-donating triarylamine units, capable of aggregation into conducting fibers triggered by light, with electron-accepting entities to obtain supramolecular heterojunctions. These objectives were attained, that is in static versions (with constant distances between electron-donating and -accepting channels) and in a dynamicversion wherein the distance between the electroactive units changes owing to the controlled action of an integrated molecular muscle. These functional self-assembled systems showed very important changes in their optoelectronic properties in response to orthogonal stimuli such as light and pH.
16

Redox-coupled Spin Transition in Co(2+/3+) Complexes with Triarylamine-substituted Polypyridyl-based Ligands

Schnaubelt, Linda 08 August 2019 (has links)
The present PhD thesis describes the synthesis and characterisation of Co(2+/3+) complexes with triarylamine-substituted polypyridyl-based ligands. A light- or temperature-induced intramolecular electron transfer between the Co and the triarylamine moieties was found in the tri-cationic complexes, which was examined with electrochemical measurements, DFT calculations, optical and dynamic 1H NMR spectroscopy. This process is coupled to a high-spin <--> low-spin transition on the metal. The emphasis of this PhD thesis was the adjustment of a redox equilibrium between the paramagnetic ([Co2+(L+)(L)]3+) and diamagnetic ([Co3+(L)2]3+) formulation (L = triarylaminedecorated ligands) via the electron transfer. The position of this equilibrium is influenced by the complexes' structure and environment. Constitutional changes in the ligand topology were performed to modify the electronic properties of the triarylamine substituents and to vary the distance between the redox centres, namely the Co ion and the triarylamine nitrogen atom. If they are located within their van-der-Waals radii, photochemical excitation of the diamagnetic ground state leads to the paramagnetic excited state. A temperature-dependent redox equilibrium was found with an increased distance between the redox centres (d = 8 Å), due to the different entropies of the redox isomers.
17

Supramolecular polymers of triarylamines : studies in aqueous medium and covalent capture of their self-assemblies / Polymères supramoléculaires de triarylamines : stabilisation des structures auto-assemblées et études en milieu aqueux

Liang, Ting 13 January 2017 (has links)
Pour contrôler les systèmes chimiques complexes, les outils de la chimie supramoléculaire s’avèrent puissants et représenteront certainement une des technologies clef du 21e siècle. En effet, la réversibilité intrinsèque des liaisons chimiques impliquées dans la formation d'assemblages supramoléculaires apporte à ces systèmes un caractère "adaptatif", capable de réorganiser leur structure en fonction des conditions environnementales. Ce comportement s’avère totalement inédit malgré le grand nombre d’études effectuées sur cette famille de molécules du fait de ses propriétés photoactives. Au cours des dernières années, notre groupe a synthétisé de nombreux dérivés de triarylamines (TAAs), qui ont été utilisés pour produire des architectures supramoléculaires multifonctionnelles. En fonction des différents groupements qui substituent ce coeur TAA, diverses morphologies ont pu être observées et les propriétés physiques de ces auto-assemblages produits dans des solvants non polaires tels que les solvants chlorés ou le toluène se sont également révélées variées (propriétés cristal-liquide, conductrices, plasmoniques...). A partir de ces travaux, mon projet de thèse consistait en deux objectifs: a) étudier l'auto-assemblage et les propriétés de ces composés TAA dans des solvants polaires comme l'eau ou le méthanol. Pour cela, comme tenu du caractère hydrophobe des TAAs, il s'avérait nécessaire de synthétiser de nouvelles molécules incorporant des groupements latéraux favorisant la solubilité dans de tels solvants; b) stabiliser les auto-assemblages de triarylamine par polymérisation covalente et étudier les propriétés physiques associées à ces nouvelles structures. Pour cela, il convenait de synthétiser de nouvelles molécules incorporant des groupements polymérisables sur les chaines latérales, qui n'influençaient pas les propriétés d'auto-assemblages des TAAs. [...] / Based on the unique directionality and reversibility of non-covalent interactions, supramolecular self-assembly works as an elegant methodology to construct multifunctional hierarchical architectures. Inspired by nature, where water provides a vital environment for biological process such as biomacromolecular folding, water-soluble supramolecular polymers have been prepared and studied so as to mimic related biological systems. On the other hand, owing to the dynamic nature of their non-covalent bonds, supramolecular polymers often lack mechanical robustness. Thus, cross-linking strategies have been developed in order to combine highly ordered molecular arrangement inherent to the sef-assembly and mechanical robustness of the covalent backbone, which might bee promising to reach functional materials for practical applications. In this thesis, we focus on well-designed triarylamine molecules which are known to self-assemble into supramolecular polymers with excellent physical properties, as discovered by our group. In particular, molecules studied in this manuscript are based on tris-amide triarylamine scaffold known to produce self-assemblies with metallic conductivity and self-healing behavior. First, we studied the self-assemblies of three novel tris-amide triarylamine derivatives decorated with either poly(ethylene glycol) (PEG), peptide or cyanine dyes side chains on the three amide positions in polar solvents, i.e. either water or methanol. Characterizations by various physico-chemical techniques (NMR, UV-Vis absorption, fluorescence, infrared spectroscopies, microscopies, scatterings) demonstrated the formation of fibrillar aggregates for all molecules in such polar environments. Overall, this study suggest that the triarylamine core act as the main driving force for the self-assembly into columnar aggregates while side chains ensure solubility in these solvents and/or favor the formation of chiral architectures. In a second study, we investigated the formation of tris-amide triarylamine supramolecular polymers decorated with norbornene and siloxane end side chains, which could be further used to freeze the self-assembled structures by ring opening metathesis polymerization and sol-gel methods, respectively. [...]
18

Electron transfer and delocalization in mixed-valence monocations of bis- and tris-(diarylamino) derivatives

Odom, Susan A. 18 November 2008 (has links)
To better understand the optical and electronic properties of thiophene- and pyrrole-based organic compounds on a molecular level, several aromatic compounds and their corresponding monocations were analyzed by a variety of solution-based spectroscopic techniques. The derivatives were initially synthesized using palladium-catalyzed amination reactions, condensation reactions, Horner-Emmons reactions, and Stille coupling reactions. Once isolated, the neutral compounds were analyzed by UV-visible-NIR absorption spectroscopy, fluorescence spectroscopy, cyclic voltammetry, and / or differential pulse voltammetry. Monocations were generated by chemical oxidation and were analyzed by visible-NIR absorption spectroscopy and electron paramagnetic resonance spectroscopy. By quantifying the extent of the electron-donor abilities of some chromophores and the electron delocalization of positive charge in the monocations, a more thorough understanding of the optical and electronic properties of the compounds was obtained.
19

Development of Functional Organic Materials Using Oxygen-Bridged Triarylamine Skeleton as Quasiplanar Structure / 準平面型構造を有する酸素架橋トリアリールアミン骨格に基づいた機能性有機材料の開発

Nishimura, Hidetaka 23 March 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19736号 / 工博第4191号 / 新制||工||1646(附属図書館) / 32772 / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 村田 靖次郎, 教授 大江 浩一, 教授 小澤 文幸 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
20

Supramolecular self-assemblies of triarylamines : fundamental studies and applications / Aspects fondamentaux et appliqués d'auto-assemblage supramoléculaires de triarylamines

Osypenko, Artem 26 September 2016 (has links)
Dans cette thèse, nous avons étudié le mécanisme fondamental du processus d'auto-assemblage thermoréversible des trisamides triarylamines chiraux. Nous avons ensuite étudié les utilisations possibles de dérivés de triarylamine dans différents domaines de recherche liés à la science des matériaux. Premièrement, en utilisant une approche biocatalytique, nous avons réussi à contrôler l'auto-assemblage d’amphiphiles à base de TAA-peptide conjugués dans l'eau. Deuxièmement, de nouveaux dérivés de triarylamine ont été incorporés avec succès en tant que couches conductrices de trous dans des cellules solaires de type pérovskite. Troisièmement, nous avons démontré la possibilité de déclencher électrochimiquement l'auto-assemblage de triarylamines pour la construction anisotrope contrôlée de nanofils conducteurs. Enfin, nous avons développé une technique qui permet l'alignement hautement ordonné de nanoparticules d'or sur une couche de nanofils de triarylamines à l'interface liquide-liquide. / In this thesis, we have explored the fundamental mechanism of the thermally initiated self-assembly process of chiral triarylamine trisamides. The results demonstrate a cooperative nucleation and growth mechanism with well-defined thermal hysteresis and memory effect. We have then studied the possible implementations of triarylamine derivatives in various fields of material sciences. First, by taking advantage of a biocatalytic approach, we managed to control the self-assembly of TAA-peptide amphiphiles in water. Second, new triarylamine derivatives were successfully inserted as hole transporting layers in perovskite solar cells. Third, the self-assembly of triarylamines was triggered electrochemically, leading to an anisotropic construction of conducting nanowires. Finally, we developed a technique that allows for the highly ordered alignment of gold nanoparticles over a layer of triarylamine nanowires at the liquid-liquid interface by simple centrifugation of a biphasic mixture.

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