Die vorliegende Arbeit behandelt Fragestellungen aus der Organischen Elektronik, in der die Ladungsträgerinjektion in alle Arten von Bauteilen kritisch von der elektronischen und morphologischen Struktur der Grenzflächen zwischen Elektrode und den konjugierten organischen Molekülen (KOM) abhängt. Näher betrachtet wurden: die Energieniveauanpassung mit starken (i) Elektronendonatoren und (ii) -akzeptoren und (iii) die dichteabhängige Umorientierung einer molekularen Monolage. Zur Analyse wurden Photoelektronen- und Reflektionsabsorptionsinfrarotspektroskopie angewandt. Weitere Informationen konnten durch Modellierung mit Dichtefunktionaltheory gewonnen werden, die über Kollaborationen zur Verfügung standen. (i) Das Konzept der optimierten Energieniveauanpassung mit starken Elektronenakzeptoren konnte auf Donatoren erweitert und damit erfolgreich von der Anode zur Kathode transferiert werden. Auch hier führte der Ladungstransfer zu einem Dipol über die Grenzfläche, womit die Austrittsarbeit um bis zu 2.2 eV reduziert wurde. Als Resultat konnte die Elektroneninjektionsbarriere in nachfolgende Materialien entscheidend verringert werden (bis zu 0.8 eV). (ii) Ein bis dato unerforschter starker Elektronenaktzeptor [hexaaza-triphenylene-hexacarbonitrile (HATCN)] wurde vollständig verschiedenen Elektroden charakterisiert. HATCN zeigte dabei eine bessere Performance verglichen mit derzeit üblichen Materialien (starke Austrittsarbeitsanhebung und Verringerung der Lochinjektionsbarriere um bis zu 1.0 eV). (iii) Zusätzlich konnte mit HATCN gezeigt werden, dass eine liegende molekulare Monolage durch Erhöhung der Moleküldichte in eine stehende Monolage umgewandelt werden kann. Dies führte zu einer Änderung der chemischen Bindung zum Metall und damit zu einer starken Modifikation der elektronischen Struktur der Grenzfläche. Die vorliegende Arbeit liefert damit wertvolle Informationen für das Verständnis der Grenzfläche zwischen Elektrode und KOM in der Organischen Elektronik. / The present work is embedded in the field of organic electronics, where charge injection into devices is critically determined by the electronic and structural properties of the interfaces between the electrodes and the conjugated organic materials (COMs). Three main topics are addressed: energy level tuning with new and strong electron (i) donor and (ii) acceptor materials and (iii) the density dependent re-orientation of a molecular monolayer and its impact on the energy level alignment. To study these topics photoelectron and reflection absorption infrared spectroscopy were used. Moreover, additional information was obtained from density functional theory modelling, which was available through collaboration. (i) A concept of optimizing the energy level alignment at interfaces with strong molecular acceptors was extended to donor materials and thus successfully transferred from the anode to the cathode side of the device. Also in this case, charge transfer leads to a chemisorbed molecular monolayer. Due to the dipole across the interface, the work function of the electrode is reduced by up to 2.2 eV. Consequently, a reduced electron injection barrier into subsequently deposited materials is achieved (up to 0.8 eV). (ii) A yet unexplored strong electron acceptor material [i.e. hexaazatriphenylene- hexacarbonitrile (HATCN)] is thoroughly investigated on various surfaces. HATCN shows superior performance as electron acceptor material compared to presently used materials (e.g. work function modification and hole injection barrier reduction by up to 1 eV). (iii) Also with HATCN, the orientation of a molecular monolayer is observed to change from a face-on to an edge-on depending on layer density. This is accompanied by a re-hybridization of molecular and metal electronic states, which significantly modifies the interface electronic properties. All findings presented are valuable for the understanding of electrode-COM interfaces in organic electronics.

In der heutigen Zeit sind optoelektronische Bauelemente allgegenwärtig. Sie finden Anwendung für Beleuchtungszwecke, in Anzeigen und für die Telekommunikation. Die Entwicklung dieser Anwendungen wurde lange Zeit von anorganischen Halbleitern getragen, in jüngerer Vergangenheit auch von der organischen Elektronik. Neuerdings werden verstärkt Konzepte entwickelt, um die spezifischen Vorteile der jeweiligen komplementären Materialklassen auszunutzen. Für diese Hybridisierung müssen die Eigenschaften der verschiedenen Materialien, insbesondere die elektronische Struktur, genau auf einander abgestimmt sein. In dieser Arbeit werden Leiter-para-phenylene auf spektrale Überlagerung und angepasste Orbitalenergien mit ZnO, auf chemische Inertheit und auf die Bildung von dünnen Schichten über vakuumbasierte Verarbeitungsmethoden optimiert. Dazu konzentriert sich der synthetische Gesichtspunkt auf die selektive Funktionalisierung der verschiedenen Methylenbrücken mit Alkyl-, Aryl- und Fluorsubstituenten. Die finalen Stufen werden bezüglich ihrer optischen Eigenschaften mittels Absorption und Fluoreszenz, bezüglich ihrer elektrochemischen Eigenschaften und bezüglich ihrer Festkörperstruktur mittels Röntgenstrukturanalyse von Einkristallen charakterisiert. Außerdem widmet sich ein erheblicher Teil dieser Arbeit der Erforschung des photochemischen Abbaus von fluorenbasierten Strukturen. Es werden neue Erkenntnisse zum Abbaumechanismus und der Ursache der grünen Emission gewonnen. Weiterhin werden die Abbauraten von Fluorenstrukturen mit verschiedenen Brückensubstituenten verglichen. Dabei konnten auch verschiedene Reaktionsprodukte und Mechanismen nachgewiesen werden. Letztendlich wird auch die Anwendung einzelner Derivate in Hybridstrukturen diskutiert. / Nowadays optoelectronic devices are ubiquitous for illumination purposes, in telecommunication and displays. For a long time, the development for these devices was driven by inorganic semiconductors, later organic semiconductors contributed, as well. Recently concepts have been developed to combine both complementary material classes to exploit the specific advantages of each one. For the hybridization, the properties of the materials, especially the electronic structure, have to match very well. In this work the optimization of ladder-type p-phenylenes towards spectral overlap and energy level alignment with ZnO, vacuum-processability, inertness, as well as layer formation is described. In terms of molecular design the different properties are addressed by site-selective functionalization of the methylene bridges with alkyl, aryl, and fluoro groups. The final products are characterized regarding their optical properties by absorption and fluorescence, their electrochemical properties, as well as their solid-state structure by single crystal X-ray diffraction. Apart from that, a large part of the work is devoted to investigations of the photochemical degradation of fluorene-type structures. New insights are gained into the mechanism of degradation, as well as the origin of the green emission in ladder-type structures The dependence of the rate of degradation is described semi-quantitatively with respect to the substitution pattern. By that, different reaction mechanisms for different substituents are found. Finally, the integration of some products in hybrid structures is discussed.

Células eletroquímicas poliméricas emissoras de luz, PLECs, são dispositivos eletrônicos orgânicos que vêm despertando muito interesse comercial por operarem sob baixa tensão com alto desempenho e sem a necessidade de eletrodos específicos, como o óxido de estanho e índio (ITO), cálcio entre outros. Esta característica confere a possibilidade de processamento de baixo custo e de obter dispositivos flexíveis. Nas PLECs a injeção de portadores eletrônicos de carga nas interfaces, entre a camada ativa do dispositivo e seus eletrodos, é facilitada por ação de espécies iônicas, que são inseridas no material polimérico por adição de um sal. Do ponto de vista científico, o interesse atual reside na completa compreensão dos fenômenos de transporte de portadores eletrônicos no interior do dispositivo. Hoje existem dois modelos concorrentes. Um considera o transporte eletrônico por difusão e o outro leva em consideração a dopagem eletroquímica e a consequente formação de uma junção PIN (semicondutor dopado tipo-p camada isolante semicondutor dopado tipo-n). Nesse contexto, propusemos a fabricação e caracterização elétrica de PLECs com diversas composições e espessuras a fim de confrontar os resultados experimentais com os modelos em questão. Demonstramos a existência de uma concentração crítica de sal, abaixo da qual a operação da PLEC é promovida predominantemente por injeção auxiliada pela formação de duplas-camadas devido ao movimento iônico. No regime de tensões mais elevadas, além da injeção, ocorre a dopagem tipo-p e tipo-n e a formação da junção PIN. Além disso, determinamos que para tensões superiores à de operação o dispositivo apresenta comportamento ôhmico, com resistência elétrica proporcional à espessura do dispositivo e praticamente independente da temperatura. Nossos resultados mostraram que no regime de tensões mais baixas deve ocorrer um processo de transporte por difusão, mas à medida que a tensão aumenta, inicia-se um processo de dopagem tipo-p de um lado e tipo-n de outro, aumentando a condutividade das regiões dopadas e finalizando com a formação de uma junção PIN. Mostramos também que a tensão acumulada nas duplas-camadas independe do tipo de polímero eletrônico, e que a tensão de operação, aquela na qual o polímero luminesce, é semelhante á do gap da banda proibida do polímero luminescente. / Polymer light emitting electrochemical cells, PLECs, are organic electronic devices that have attracted commercial interest because they operate at low voltage and exhibit high performance without the need of specific electrodes such as indium tin oxide (ITO), calcium and others. This feature provides low cost of fabrication and exible devices. The charge injection in the PLECs is facilitated by the action of ionic species, which are inserted in the polymeric material by adding a salt. This thesis treats with a controversy related to transport phenomena along the bulk of the device. Currently, there is two opposite models. One that considers that transport is driven by diffusion mechanism; and the other takes into account the formation of a PIN junction (p-type semiconductor insulating layer n-type semiconductor). Here, we proposed the fabrication and characterization of PLECs having different compositions and thickness, and the results were faced up to the models. We showed the existence of critical concentration of salt, below of which the operation of the PLECs are mainly due to injection stimulated by the ionic double-layer. For higher applied voltages, the injection still exists but it is followed by a PIN junction formation. We also verified that for voltages above the turn-on the device electrical resistance is proportional to the sample thickness and is practically temperature-independent. Our results showed that for low voltages the transport is dominated by diffusion, but as the voltage increases, the semiconducting layer starts to be doped: p-type in one side, and n-type in the other. Therefore, the conductivity of the semiconducting layer increases, and it finalizes by the formation of the PIN junction. Finally, we showed that the double-layer characteristic does not depend on the electronic polymer, and that the value of the turn-on voltage is very close to that of the electronic gap of the forbidden band.

A tecnologia dos semicondutores inorgânicos tem dominado a indústria eletrônica por muitos anos. No entanto, com a descoberta dos polímeros condutores um esforço considerável tem sido dedicado ao estudo e às aplicações tecnológicas desses materiais em dispositivos eletrônicos, dando início a um novo ramo da eletrônica: a Eletrônica Orgânica (EO). Uma das grandes vantagens da EO reside nos métodos de processamento. Os materiais orgânicos são facilmente processados em solução, portanto permite o uso de diversas técnicas de deposição, como por exemplo, as técnicas de impressão. Dentre as técnicas de impressão, a jato de tinta é a que mostra ser mais adequada à impressão de circuitos. Ela permite depositar volumes de soluções (ou suspensões) da ordem de picolitros em cada gota mantendo padrões bem definidos. Além disso, elimina o uso de máscaras, ocasionando diminuição nos custos e desperdício de material e, por ser um método de deposição tipo não-contato, minimiza possíveis contaminações. Esta tese dedicou-se, dentro desse contexto, ao domínio da técnica de jato de tinta para a confecção de transistores de efeito de campo orgânico (OFETs) tipo p e tipo n, e com aplicação em um inversor lógico unipolar. Os OFETs impressos usaram a arquitetura top gate/bottom contact (TG/BC. Os filmes semicondutores foram formados por várias linhas impressas sobre a região dos eletrodos fonte e dreno. Para os OFETs tipo p foi utilizado o semicondutor Poli(3-hexiltiofeno) régio-regular (rr-P3HT). Foram fabricados OFETs tipo p com a impressão de linhas utilizando os quatro diferentes padrões de deposição da impressora Autodrop. OFETs tipo p com mobilidade em torno de 3x10-3 cm2/V.s e razões Ion/Ioff da ordem de 103 foram obtidos utilizando um padrão de deposição paralelo e outro perpendicular a fonte e dreno. Para os OFETs tipo n o semicondutor usado foi o Poli{[N,N\'-bis(2-octildodecil)-naftaleno-1,4,5,8-bis(dicarboximida)-2,6-diil]-alt-5,5\'-(2,2\'-bitiofeno)]} (P(NDI2OD-T2)). Dentre os OFETs tipo n impressos os melhores apresentaram mobilidades em torno de 10-2 cm2/V.s e razões Ion/Ioff de aproximadamente 5x102. Ambos os OFETs impressos foram aplicados em inversores lógicos digitais unipolares com ganhos maiores que 1. / The technology of inorganic semiconductors has dominated the industry of electronics for many years. However, since the discovery of conductive polymers considerable effort has been devoted to studies and technological applications of these materials in electronic devices, starting a new branch of electronics: Organic Electronics (OE). One of the great advantages of OE lies in the processing methods. The organic materials are easily handled in solution, thus allows the use of various deposition techniques, as for example the printing techniques. Among the techniques of printing, inkjet is showing to be more suitable for printing circuits. It allows you to deposit solutions (or suspensions) volumes on the order of picoliters in each drop, performing well-defined patterns. Furthermore, it eliminates the use of masks, resulting in reduced costs and material waste. This thesis is dedicated to the field of inkjet technique, specifically for the fabrication of organic field-effect transistors (OFETs), p-type and n-type, and application in a unipolar logic inverter. Printed OFETs used architecture top gate/bottom contact (TG/BC). The semiconductor films were formed by several printed lines on the region of the source and drain electrodes. For p-type OFETs we used poly (3-hexylthiophene ) regio-regular (rr-P3HT) as semiconducting material. The p-type OFETs were fabricated using the four different patterns of deposition of the printer Autodrop. These OFETs showed mobility around 3x10-3 cm2/V.s and Ion/Ioff ratio of the order of 103 for the deposition pattern parallel and perpendicular to source and drain. For the n-type OFETs the semiconductor used was Poly{[N,N\'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5\'-(2,2\'-bithiophene)]} (P(NDI2OD-T2)). Among the printed n-type OFETs the best showed mobility around of 10-2 cm2/V.s and Ion/Ioff ratio of the order of 5x102. Both printed OFETs were applied in unipolar digital logic inverters, with gains greater than 1.

O trabalho desta dissertação versou sobre avanços em tecnologias de eletrônica impressa de baixo custo. Em particular, aplicamos as técnicas de impressão por serigrafia e por jato de tinta para confeccionar dispositivos eletrônicos e optoeletrônicos. O primeiro dispositivo construído foi resistências impressas por jato de tinta tendo como matérias primas o poli(3,4-etileno dióxido tiofeno) com sulfonato de poliestireno (PEDOT:PSS) e nanopartículas de prata sobre substratos de vidro. Os valores das resistências foram analisados em se variando parâmetros de impressão. Como segundo dispositivo, imprimimos pela técnica de serigrafia sobre vidro e kapton, antenas de cartões de RFIDs (Radio-Frequency Identifications), também com os dois materiais: tinta de prata e PEDOT:PSS. Os RFIDs foram projetados para operar em frequências entre 860 MHz e 960 MHz. A antena de PEDOT:PSS mostrou alcance de 0,45 m, enquanto que a de tinta prata teve alcance de 1,6 m em 860 MHz e de 4 m em 960 MHz. Fabricamos também células eletroquímicas emissoras de luz (Organic Light Emitting Electrochemical Cells - OLECs), no qual substituímos o eletrodo transparente de óxido de índio (ITO), por um feito de PEDOT:PSS, aplicado por serigrafia sobre vidro. A camada ativa da célula luminescente foi feita por uma mistura de óxido de polietileno complexado com sal de lítio e um polímero luminescente derivado de polifluoreno que emite no verde. As curvas características de corrente e luminância em função da voltagem externa aplicada mostrou o bom desempenho das células fabricadas. Finalmente, produzimos células fotovoltaicas orgânicas, em que o eletrodo transparente, também de PEDOT:PSS, foi depositado por serigrafia sobre vidro. A camada ativa nesse caso foi um sistema bifásico feito de poli(3hexiltiofeno) (P3HT) e um éster, o [6,6]-fenil-C61-ácido metil-butírico (PCBM). Esse dispositivo apresentou um Fator de Preenchimento de 0,47 e uma eficiência externa de aproximadamente 2%. / The work developed along this thesis presents advances in printed electronic technologies of low cost. In particular we applied printable serigraphic and Inkjet technologies to produce electronic and optoelectronic devices. First, we produced resistances having poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) and silver paint as active materials, using an Inkjet printer on glass substrate. We made studies of the resistance performance varying some printed parameters. Then, by serigraphy screen printing was printed, on substrates of kapton and glass, an antenna in an Radio-Frequency Identification card (RFID), also from PEDOT:PSS and from silver paint. This RFID was projected to operate in a frequency range from approximately 860 MHz to 960 MHz. The antenna made of PEDOT:PSS operated in a distance of 0.45 m, while that of silver varied from 1.6 m at 860 MHz to 4 m at 960 MHz. In an Organic Light Emitting Electrochemical Cell (OLEC) we applied one of the electrodes, a PEDOT:PSS layer, as a transparent electrode by serigraphy on glass substrate for made to replace of ITO. The active layer was a mixture of a poly(ethylene oxide) complexed with lithium salt and a derivative of polyfluorene that is a green emitter. The characteristic curves of current and luminance against the applied external voltage assured us the good performance of the device. Similar result was obtained with the performance of an organic photovoltaic (OPV), in which the active layer was a biphasic system made by poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), in which the transparent electrode (PEDOT:PSS) was also printed by serigraphy on glass substrate. In this device we obtained a Fill Factor of 0.47 and an external efficiency of almost 2%.

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No. of bitstreams: 1 torikai_K_me_bauru.pdf: 9782713 bytes, checksum: 3775eee15d15983b2b404989e8170b7b (MD5) Previous issue date: 2018-12-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A eletrônica orgânica mostrou-se comercialmente viável e competitiva, já sendo integrada em diversas tecnologias, e.g., displays flexíveis de OLED, painéis solares de grande área, dispositivos biocompatíveis/vestíveis, entre outras. A utilização de materiais orgânicos na fabricação de dispositivos eletrônicos explora vantagens como: flexibilidade mecânica, baixas temperaturas de processamento e possibilidade de se implementar melhorias e ajustes por meio de sínteses químicas. Entretanto, a eletrônica inorgânica já bem estabelecida ainda se destaca na área da eletrônica robusta, uma vez que os semicondutores orgânicos (OSCs) são bastante suscetíveis a condições mais extremas, como exposição a gases e radiação. Nesse sentido, a tecnologia de nanomembranas autoenroladas (NM) tem mostrado, nos últimos anos, um grande potencial na fabricação de dispositivos híbridos ultracompactos em uma arquitetura inédita para transistores orgânicos de filmes finos (OTFTs). A partir das técnicas tradicionais de microfabricação—fotolitografia, deposição de filmes finos—fabricou-se OTFTs sobre NMs que, uma vez liberadas do substrato através da remoção sistemática de uma camada de sacrifício, remodelam os dispositivos em uma arquitetura tubular tridimensional, reduzindo a área ocupada em aproximadamente 90% e protegendo os OSCs da área ativa do OTFT entre as múltiplas voltas das NMs. Assim, mostrou-se que a arquitetura confere novas propriedades aos OTFTs sem prejudicar as propriedades elétricas, suportando centenas de ciclos de compressão mecânica e mostrando-se resistentes a radiação ultravioleta e a vapores agressivos, como a amônia. Por fim, para validar a arquitetura de OTFT inédita, mostra-se que a estratégia utilizada é válida para diferentes OSCs e pode ser utilizada na fabricação de circuitos eletrônicos mais complexos a partir da associação de múltiplos dispositivos, como o inversor aqui apresentado. / In the recent years, the organic electronics’ commercial viability and competitiveness became apparent, integrating a diversity of technologies, e.g., OLED flexible displays, large-area solar panels and biocompatible and wearable devices. The manufacturing of electronic devices with organic materials aims at exploiting inherent characteristics— mechanical flexibility, low processing temperatures and the potential of boosting and tailoring specific properties through chemical synthesis. However, there’s still a gap between the well-established inorganic and the organic electronics concerning applications on rugged electronics, since the organic semiconductors (OSCs) are very susceptible to harsh conditions, e.g., exposition to UV radiation and gases. In this sense, recent advances on strained nanomembrane (NM) technology has shown enormous potential in the manufacturing of hybrid ultracompact devices in a novel organic thin-film transistor (OTFT) architecture. Through traditional microfabrication techniques—photolithography, thin-film deposition—OTFTs were fabricated on top of strained NMs, which promotes a reshaping of the devices into a 3D tubular architecture when released from the substrate. This process promotes a reduction in about 90% of the footprint area while protecting the OSC in the active area in between the multiple device windings. Therefore, the OTFTs have been endowed with new proprieties without loss of electric performance, while enduring hundreds of mechanical compression cycles and showing increased resilience against UV radiation and hazardous vapors, such as ammonia. Finally, to validate this novel OTFT architecture, this strategy has been shown to be valid for different OSCs and can be used to manufacture electronic circuits through the association of multiple devices, such as the inverter reported in this study. / CAPES: Código de financeamento 001 / FAPESP: Jovem Pesquisador 2014/25979-2

L’électrophysiologie est l’étude des signaux électriques et électrochimiques générés par certaines cellules spécifiques tout comme par des organes entiers. Elle donne aux médecins l’opportunité de suivre le fonctionnement d’un seul neurone mais aussi de l’intégralité du cerveau. L’enregistrement de ces activités est essentiel pour le diagnostic de pathologies aussi diverses que les arythmies cardiaques, l’épilepsie ou la dégénération musculaire. Dans cette thèse, nous étudions différents types d’électrodes cutanées à base de matériaux organiques, de leur conception à leur évaluation préclinique. Notre approche est basée sur l’utilisation du polymère conducteur PEDOT :PSS et de gels ioniques, qui réduisent l’impédance de l’interface électrode-peau. De plus, nos électrodes sont conçues avec différents substrats fins et souples, plastiques ou textiles. Ceci appelle de nouvelles techniques de fabrications adaptées à ces substrats et aux matériaux organiques. Les électrodes sont caractérisées puis testées sur des volontaires afin de démontrer leurs excellentes performances par rapport aux électrodes médicales usuelles. L’évaluation de leur capacité à réduire le bruit et de leur stabilité sur plusieurs jours est effectuée sur des signaux venant des activités musculaires, cardiaques et cérébrales. Nous présentons également une électrode microscopique dite « active », basée sur le transistor organique électrochimique. Celui-ci permet d’amplifier et de filtrer in situ le signal. Parce que nos électrodes organiques cutanées possèdent un important potentiel industriel et clinique, nous étudions maintenant leur intégration dans des dispositifs médicaux de pointe. / Electrophysiology is the study of electrical and electrochemical signals generated by specific cells or whole organs. It gives doctors the opportunity to track the physiological behavior of a single neuron, as well as the integral brain. The recording of these activities is essential to diagnose and better understand diseases like cardiac arrhythmias, epilepsy, muscular degeneration and many more. In this thesis, we study different types of cutaneous electrodes based on organic materials, from conception to pre-clinical evaluation. Our approach is based on the usage of PEDOT:PSS conducting polymer and ionic gels in order to reduce impedance at the skin-electrode interface. Moreover, the substrate of our electrodes is made with different materials such as thin and conformable plastics and textiles. Our devices are then flexible, motion resistant and can be integrating into clothes. We developed new fabrication processes, considering the different substrates and organic materials specifics. The electrodes were characterized and then tested on human volunteers to show their excellent performance in comparison to standard medical electrodes. The evaluation of noise reduction capabilities and possibilities to perform long-term recordings were established on signals coming from muscles, heart and brain. Furthermore, we present a hundred micrometer-small “active” electrode, based on the organic electrochemical transistor. It enables in situ amplification and filtering of recorded signals. The wearable organic electrodes developed in this work are of great industrial and clinic interest. Future work will aim to integrate these technologies into state-of-the-art medical devices.

Ce travail visait à explorer les interactions supramoléculaires comme un outil dans les domaines de la chimie hôte-invité, les nanomatériaux et les nanotechnologies en général, afin de parvenir à des objectifs différents. D'abord, une interaction classique hôte-invité a été étudiée, au moyen d'une technique innovante telle que l'ITC, puis nous avons exploité les interactions supramoléculaires afin de maitriser la production de graphène exfolié en phase liquide, en mettant un accent particulier sur l'amélioration de la qualité et la quantité du matériau produit. Enfin, nous avons étendu l'utilisation de la chimie supramoléculaire à un dispositif réel par la fonctionnalisation des électrodes d'or avec des molécules photochromiques, ouvrant alors la voie à des dispositifs organiques multifonctionnels, pouvant être contrôlés par la lumière. / This work was aimed at exploring supramolecular interactions as a tool in the fields of host-guest chemistry, nanomaterials and in general nanotechnology, in order to achieve different goals. First, a classical host-guest interaction was studied by means of the ITC technique, then we exploited supramolecular interactions in order to harness the production of liquid-phase exfoliated graphene, with a particular focus on improving the quality and quantity of material produced. Finally, we extended the use of supramolecular chemistry to a real device by functionalization of gold electrodes with photochromic molecules, hence paving the way towards multifunctional organic devices and in prospective to graphene based light-controlled multifunctional devices.

Cette thèse a pour but d’étudier le transport de porteur de charge au sein de polymères conjugués, avec comme finalité d’identifier les propriétés des appareils d’électronique organique appropriées pour des applications dans la spintronique organique. Nous avons analysé des échantillons planaires, de géométries latérales, qui offrent la possibilité d’étudier les propriétés de transport sous l’application de différents stimulus et la détection le transport de longue distance du moment angulaire (spin), au sein de semi-conducteurs organiques (OSC). Dans cette configuration, des critères bien établis doivent être satisfait pour réaliser le transport diffusif d’un courant de spin polarisé au travers d’un matériel organique. Nous avons analysé ces diffèrent critères et trouvé des matériaux dont les propriétés physiques fournissent une solution satisfaisante. Le résultat de ce travail fut la création de transistors à effet de champ organiques dont les propriétés répondent au besoin des applications de spintronique. / In this thesis, charge carrier transport in conjugated polymers is studied with the aim to identify organic electronics devices properties suitable for applications in organic spintronics. We investigate planar samples, in a lateral geometry, which offer the possibility to study transport properties under the application of different stimuli and to detect long-range spin transport in OSCs. In this configuration, well-established criteria must be satisfied to realize diffusive-like transport of a spin-polarized current through an organic material. We analyse these criteria and find possible materials properties solutions. The outcome is the realization of organic field-effect transistors with properties ad hoc for spintronics applications.

Le lien entre la structure semi-cristalline et les propriétés d’usage (mécaniques, diélectriques et électro-actives) de films de copolymères fluorés électro-actifs développés pour des applications en électronique organique imprimée a été étudié. Les matériaux investigués sont des copolymères poly(VDF-co-TrFE) et des terpolymères poly(VDF-ter-TrFE-ter-CTFE) à base de fluorure de vinylidène (VDF), trifluoroéthylène (TrFE) et chlorotrifluoroéthylène (CTFE).Les films de polymères obtenus par évaporation du solvant sont étudiés par diffraction des rayons X (SAXS-WAXS), DSC, FTIR, DMA, spectroscopie diélectrique et cycles de polarisation afin de mettre en évidence l’impact de la composition et de la mise en forme (recuit, polarisation) sur la structure et les propriétés finales du matériau. Nous montrons ainsi qu’au sein des films de copolymères, la phase ferroélectrique (FE) coexiste avec une phase ferroélectrique défective (DFE). La fraction croissante de cette phase DFE avec la teneur en TrFE permet d’expliquer l’évolution des propriétés thermiques dont la transition de Curie. Une transition structurale continue, de la phase DFE vers la phase paraélectrique (PE), en température a été mise en évidence.La teneur en termonomère CTFE influence fortement la structure cristalline et les propriétés électro-actives des films de terpolymères (disparition du caractère ferroélectrique au profit du caractère ferroélectrique relaxeur (RFE)). Nous prouvons pour la première fois l’existence d’une transition structurale continue entre la phase RFE et la phase PE au voisinage de la température ambiante. Cette transition permet d’expliquer les propriétés exacerbées de ces matériaux (constante diélectrique et déformation sous champ électrique). Enfin, des analogies de comportement entre les copolymères et les terpolymères sont discutées, notamment l’évolution des phases cristallines sous champ électrique, afin de mieux comprendre le fonctionnement de ces polymères électro-actifs pour leur futur développement au niveau industriel. / The relationship between semi-crystalline structure and properties of use (mechanical, dielectric and electroactive) of fluorinated copolymer films was studied for applications in organic electronics. Investigated materials are poly(VDF-co-TrFE) copolymers and poly(VDF-ter-TrFE-ter-CTFE) terpolymers based on vinylidene fluoride (TrFE), trifluoroethylene (TrFE) and chlorotrifluoroethylene (CTFE). Polymer films, obtained after solvent evaporation, are studied by X-ray diffraction (SAXS-WAXS), DSC, FTIR, DMA, dielectric spectroscopy and polarization cycles in order to highlight the impact of composition and processing (annealing, poling) on structure and final properties of material. We showed that the ferroelectric (FE) phase coexists with the defective ferroelectric (DFE) phase in copolymer films. The increasing fraction of DFE phase with TrFE content allows explaining the evolution of thermal properties. A continuous structural transition, from DFE phase to paraelectric (PE) phase was highlighted. The CTFE termonomer content highly influences the crystalline structure and the electro-actives properties of terpolymer films (loss of ferroelectric behavior in favor of relaxor ferroelectric (RFE) behavior).We proved for the first time the existence of a continuous structural transition between RFE phase and PE phase around room temperature. This transition allows explaining exacerbated properties of these materials (dielectric constant and deformation under electric field).Finally, analogies of behavior between copolymers and terpolymers are discussed, especially the evolution of crystalline phases under electric field, in order to better understand how these electro-active materials work for their future development at industrial level.