Techn. University, Diss., 2005--Dresden.

Filmes de politiofeno foram eletroquimicamente depositados em diversos substratos eletródicos em meio aquoso fortemente ácido e as características dos materiais formados foram estudadas através de técnicas voltamétricas, espectroscópicas (FTIR e UV-Vis. e raios X) e por microscopia eletrônica de varredura. As propriedades foram comparadas com as de filmes sintetizados em meio não-aquoso concluindo-se que o material produzido em meio aquoso mostra-se mais adequado para a aplicação como suporte de partículas eletrocatalisadoras, por sua maior atividade eletroquímica, homogeneidade e estabilidade. Foram então incorporadas partículas de Pd e Pt que foram investigadas quanto a ação catalítica frente as reações de oxidação de hidrogênio (ROH) e redução de oxigênio (RRO) em ácido sulfúrico 2,0 M. Os materiais produzidos foram primeiramente caracterizados através de técnica de absorção de raios X, tendo sido observada a formação de aglomerados de partículas bastante pequenas que não alteram seu estado de oxidação com a mudança do potencial eletródico. Verificou-se que ambos os catalisadores apresentam uma certa atividade inicial frente a ROH, mas o desempenho não é estável devido à ocorrência de processos degradativos da cadeia polimérica. Por outro lado, observou-se que os filmes contendo Pt apresentam elevada atividade catalítica frente a RRO, substancialmente maior que a de filmes contendo Pd. O mecanismo da reação mostrou-se dependente da natureza do catalisador, sendo também influenciado pelo contato com o filme polimérico. Para a Pt em contato direto com o eletrólito, a reação ocorre com envolvimento de 4 elétrons e com formação de água como produto final. Para o caso em que as partículas de Pt são recobertas por politiofeno, verifica-se a participação do peróxido de hidrogênio como intermediário, sendo que somente uma certa fração do mesmo reduz-se para formar água. No caso do Pd, o processo leva à formação de peróxido de hidrogênio em baixos sobrepotenciais, que depois é reduzido, com formação de água, em sobrepotenciais mais elevados. / Polythiophene films were electrochemically grown on several electrode substrates from strong acid aqueous solutions, and the characteristics of the materials investigated using cyclic voltammetry, FTIR and UV-Vis spectroscopies, and scanning electron microscopy. Compared to the materials prepared in non-aqueous media, the polymer synthesized in aqueous media shows more adequate characteristics for using as support for electrocatalytic particles, because of its higher electrochemical activity and stability, and bulk homogeneity. Particles of Pd and Pt were electrochemically incorporated on these polymer films, and the electrocatalytic properties of such composites investigated with respect to the hydrogen oxidation (HOR) and oxygen reduction (ORR) reactions in 2.0 M sulfuric acid solutions. Previously to these kinetic studies, the composites were characterized using X-ray absorption spectroscopy from which it is seen that the catalysts are deposited as agglomerates composed of very small particles whose oxidation states are not changed by changing the electrode potential. Both catalysts present some initial activity for the HOR, but the performance is not stable due to the occurrence of a degradation process involving the polymer chain. On the other hand, it is observed that the films containing Pt show an enhanced catalytic activity for the ORR which is considerably higher than of that containing Pd. The reaction mechanism is dependent on the catalyst nature and also influenced by the contact with a polymer film coating. For Pt in direct contact with the supporting electrolyte, the reaction occurs involving 4 electrons leading to water as final product. For Pt particles covered with a polymer layer, participation of hydrogen peroxide seems to be important with only a fraction of this specie being reduced to water. In the case of Pd, the process involves formation of hydrogen peroxide at low overpotentials, which is then reduced to water at higher overpotentials.

Derivados do politiofeno são promissores para obtenção de sensores ópticos devido as suas propriedades crômicas, enquanto que polímeros azosubstituídos (azopolímeros) têm sido estudados para várias aplicações, tal como memórias ópticas. Neste trabalho procurou-se unir as propriedades dos derivados politiofênicos as dos azopolímeros através da preparação de um polímero tiofênico azosubstituído, obtido pela funcionalização do monômero tiofênico com um grupo azobenzênico. Para fins de comparação, foram também sintetizados um derivado polialquiltiofeno, o poli(3-octiltiofeno), e um copolímero formado a partir da união dos monômeros 3- octiltiofeno e do tiofeno azosubstituído. A obtenção do monômero azosubstituído foi feita a partir de uma reação de esterificação entre o ácido 3-tiofeno acético e o corante comercial vermelho disperso 1 (disperse red 1, DR1), ao passo que o monômero alquilado foi adquirido comercialmente. Os polímeros foram sintetizados por polimerização oxidativa com cloreto fénico e caracterizados químicoestruturalmente pelas técnicas de FTIR, 1H RMN, análise elementar, HPSEC e análise térmica (TG e DSC). Dessas análises comprovou-se a formação dos homopolímeros, mas não foi possível confirmar a formação do copolímero e ainda para esse caso, obteve-se uma menor quantidade de unidades azosubstituídas do que a pretendida. A análise da fotoluminescência destes materiais mostrou a influência do tipo de cadeia lateral na intensidade e no formato do espectro de emissão desses polímeros. A espectroscopia de UV-Vis foi utilizada para o estudo de suas propriedades crômicas, sendo observada a presença de termo- e solvatocromismo. O termocromismo foi analisado em solução e na forma de filmes e o solvatocromismo em soluções de solventes puros e em misturas de THF/ n-hexano com diferentes proporções. Esses polímeros também apresentaram alterações em seus espectros de absorção como resposta à variação do pH da solução. A birrefringência fotoinduzida, técnica de estudo visando a aplicação dos polímeros em memórias ópticas, somente foi observada para o homopolímero azosubstituído. Os resultados obtidos neste trabalho indicam que o politiofeno azosubstituído é um candidato promissor para elemento ativo em uma série de aplicações, tais como sensores de diversos tipos e em dispositivos de marcação oculta / Polythiophene derivatives are promising for optical sensors due to their chromic properties while azofunctionalized polymers have been used in several applications such as optical memories. In this work, an azosubstituted polythiophene was prepared by the functionalization of the thiophenic monomer with an azobenzene moiety in order to combine the polythiophene properties with those from the azopolymers. For the sake of comparison, a polyalkylthiophene, the poly(3- octylthiophene), and a copolymer of 3-octylthiophene and the azothiophene were synthesized. The azosubstituted monomer was synthesized by the esterification reaction of 3-thiopheneacetic acid and the commercial dye Disperse Red 1 (DRI), whilc the alkyl thiophene monomer was purchased. The polymers were prepared by oxidative polymerization reactions with ferric chloride and characterized chemically and structurally using FTIR, 1H NMR, elemental analysis and thermal analysis (TG and DSC) techniques. From these analyses, the formation of homopolymers was confirmed, but it was not possible to confirm the formation of the copolymer. In the latter, the amount of azosubstituted units was smaller than expected. The analysis of the polymers photoluminescence showed the influence of the side chain in the intensity and shape of the emission spectra. UV-Vis spectroscopy was used to study the polymer chromic properties which showed thermo- and solvatochromism. Thermochromism was analyzed in solution and in thin solid films and the solvatochromism was studied in pure solvent solutions and mixtures of THF/hexane in different ratios. These polymers also had their absorption spectra affected by changing the concentration of a protonic acid (HCI) solution. Photoinduced birefringence, aiming at optical memories applications, was only observed for the azosubstituted homopolymer. The overall results indicate that the azosubstituted polythiophene is promising as active material for several applications, such as different types of sensors and security-labeling devices

This Thesis is devoted to synthesis and characterization of conjugated polymers of three types: (i) copolymers of fluorene-based units with comonomers derived from benzene, anthracene and diphenyloxadiazole; (ii) copolymers combining new thiophene monomers carrying oxadiazole and triazole moieties with various comonomers. Copolymers are designed with the respect to the tuning the optical properties and an improvement in charge transport properties; (iii) polythiophene based polyelectrolytes of two types and the basic characterization of selected physical and optical properties is reported as well as a study of interactions with noble metal nanoparticles. An incorporation of oxadiazole side groups into the fluorene copolymers was followed by the substantial increase in the stability of emission (photoluminescence). Another increase in the emission stability was achieved by the substitution of alkyl side groups on fluorene for the aryl counterparts. Such a change resulted in almost complete suppression of the undesired green emission. Further method was the incorporation of anthracene monomeric units into the main chains which resulted in the best stabilization of emission. An experiment was also made in order to shed some light on the explanation of the mechanism of emission stabilization caused by...

京都大学 / 0048 / 新制・課程博士 / 博士(エネルギー科学) / 甲第18382号 / エネ博第294号 / 新制||エネ||61(附属図書館) / 31240 / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)教授 佐川 尚, 教授 八尾 健, 教授 萩原 理加 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DGAM

Le domaine des matériaux hybrides organiques-inorganiques prend beaucoup plus d'importance de jour en jour. Ce projet de thèse traite les avantages de ce genre de matériaux et synthétise des matériaux utilisés dans deux domaines, le premier celui de l'énergie et le second dans l'environnement.Des matériaux π-conjugués à base de poly(3-hexylthiophène) (P3HT) et de silice sont synthétisés et caractérisés. Il a été montré que l'auto-assemblage lors du procédé sol-gel favorise la polymérisation régiorégulière des motifs thiophènes au sein du matériau.D'un autre coté, des matériaux hybrides organisés (mésoporeux et lamellaires) fonctionnalisés par des groupements amines ou acides ont été préparés et caractérisés. Par des modifications chimiques simples, il a été possible de rendre ces matériaux utilisables comme résines échangeuses d’ions pour la dépollution de l'eau. Les résultats montrent que les matériaux lamellaires sodiques s'avèrent les plus efficaces. Ces mêmes matériaux sont testés au niveau de la catalyse chimique et de l'époxydation qui a ouvert plusieurs perspectives sur le sujet. / The field of organic-inorganic hybrid materials takes much more importance day by day. This thesis project addresses the benefits of such materials and summarizes the materials used in two areas, energy and environment.Π-conjugated materials based on poly (3-hexylthiophene) (P3HT) and silica were synthesized and characterized. We showed that the organization obtained thanks to self-assembly of the alkylenes chains and during the sol-gel process promote a regioregular polymerization of thiophenes units.On the other hand, organized (mesoporous and lamellar) hybrid materials functionalized with amines or carboxylic acids groups were synthesized and characterized. By chemichal modifications zwitterionic materials were and used for ions extractions from water. The results show that the layered materials containig sodium ions are the most effective for the cations extraction. These same materials were tested as catalysts for epoxidation which opened several perspectives on the subject.

Diverse conformational transitions and aggregations of regioregular head-to-tail polyhexylthiophene in different environments have been studied by means of AFM and UV-vis spectroscopy. A helical conformation of the main chain with 12 thiophenes rings per each helical turn has been proposed. Length of the particles varies from several nanometers to several hundreds nanometers and can be adjusted by the solvents composition or concentration of PATs. Such well-defined organic semiconductor 1D particles can be used as building blocks for future nanoscale and molecular level electronic devices. Oligothiophenes represent one of the most promising class of semiconductive materials for FET fabrication because of their good mobility and environmental stability. However, most of unsubstituted oligothiophenes are insoluble that suppresses their potential industrial utility. On the first stage of the work, conformation, crystalline structure, molecular packing and charge carrier mobility of the highly soluble regiochemically pure [Beta]-substituted sexithiophene were systematically studied. It was found that [Beta, Beta´]-DH6T possesses moderate PR-TRMC charge carrier mobility, but rather low field-effect mobility. The investigation showed that such a poor macroscopic electrical properties of [Beta, Beta´]-DH6T originate neither from the twist of the conjugated system nor from the crystalline disorder, but rather from low-dense crystalline packing and "wrong" molecular orientation. To overcome these obstacles two thiophene-based azomethines were designed to optimize a solubility, self-assembly, and a charge carrier mobility. The idea was to utilize the ability of the amide group to form strong hydrogen bonds in non-polar solvents and in solid state, but to be easily broken in presence of polar solvents. Thus, at the stage of a dissolution and a deposition, when the solubility is important, the hydrogen bonding can be "switched off" simply by addition of polar solvents and then, after the removal of polar additives, the self-assembly can be "switched on". It was found that incorporation of azomethine and amide moieties in the [Alpha, Omega]-position, and hexyl chains in [Beta]-position of quaterthiophene, indeed considerably improves the self-assembly properties without suppression of the solubility. Self-assembly of azomethine oligomers with (QT-amide) and without amide moieties (QT-aniline) were monitored by UV-vis, XRD, and AFM. It was found that QT-amide, processed from solution, forms highly ordered layered (terrace) structures. This aggregation mode is similar to the self-assembly of unsubstituted conjugated oligomers (such as pentacene) occurred upon their evaporation in vacuum. The sum of charge carrier mobilities (PR-TRMC data) for QT-aniline was shown to be below the detectable limit, but the mobility of QT-amide was determined to be 1.10-2 cm2 V-1 s-1. The later is comparable with the mobilities of the best organic semiconductors. All these significant differences in properties of related compounds can be attributed to the hydrogen bonding between QT-amide molecules responsible for the observed self-assembly.

This work deals with the sensor application of polythiophenes, which belong to the group of the conducting polymers. The first part focuses on sensor application of poly(3,4-ethylenedioxythiophene) (PEDOT) for ion detection in aqueous electrolytes. The advanced electrochemical quartz crystal microbalance was used for investigating the electrochemical polymerisation and the redox cycling behaviour of the polymer films deposited on the liquid facing electrode of the quartz. This method is based on impedance analysis of a piezoelectric quartz crystal. The deposited polymer mass and surface roughness parameters were estimated from the electrical impedance shift of the quartz during the polymerisation using a new calculation procedure for rough and viscoelastic films. The PEDOT data were compared with results from the electrochemical polymerisation of 2,2?-bithiophene to demonstrate the influence of the substituent on morphology and electrochemical properties in organic electrolytes. With regard to electrogravimetric sensor applications the ion exchange of the polymer in aqueous electrolytes (LiClO4, NaClO4, NaNO3, and sodium toluenesulfonate) during redox cycling was investigated. From the mass/charge balance the apparent exchanged molar mass and the absolute exchanged mass of ions were calculated. The mass balance indicated a transfer of anions and solvent during oxidation. No remarkable cation exchange in the reduction scan was observed. For all investigated electrolytes the calculated exchanged molar mass can be explained with a reversible replacement of solvent by anions during oxidation. The molar solvent/anion ratio was roughly proportional to the sizes of the species. The second part of the work describes investigations on gas sensing properties of polythiophene films prepared by a new preparation method. This two-step procedure is based on electroless polymerisation of conducting polymers. In the first step the substrate is coated with an adhesion promoter and in a second step the chemical surface polymerisation of the monomer is performed. This deposition method was combined with new patterning techniques. The basis of this process is the patterned application of the adhesion promoter which was realised either by a photoresist lacquer mask or by micro contact printing of the adhesion promoter solution. These methods provide patterning down to submicrometer scale. The sensing properties of the polythiophene films were demonstrated with chemiresistors for the redox active gases NO2 and NH3. The reaction kinetics were investigated depending on humidity and temperature. / Die Arbeit befasst sich mit der Untersuchung von Polythiophenen, einer Gruppe der intrinsisch leitfähigen Polymere, für die Anwendung als sensitive Filme in chemischen Sensoren. Ziel war es dabei, ausgewählte Aspekte des Sensoreinsatzes dieser Polymere zu beleuchten, um Wege zu einer verbesserten Sensorcharakteristik solcher Systeme aufzuzeigen. Der erste Teil der Ergebnisse konzentriert sich auf den Einsatz von Poly(3,4-ethylendioxythiophen) in Sensoren für die Bestimmung von Ionenkonzentrationen in wässrigen Medien. Die elektrochemische Polymerisation auf Schwingquarzen und der potentialinduzierte Ionenaustausch an solchen Polymerfilmen wurden mit Hilfe der elektrochemischen Quarzmikrowaage charakterisiert. Diese beruht auf der Impedanzanalyse von Schwingquarzen in der Nähe ihrer Resonanzfrequenz, was neben der Erfassung der Änderung der Resonanzfrequenz der Quarze auch die Untersuchung des Dämpfungsverhaltens und somit eine halbquantitative Analyse der mechanischen Eigenschaften des Polymerfilmes ermöglicht. Aus den Daten Impedanzanalyse während der Polymerisation wurden mit einem neuen Berechnungsmodells, das viskoelastische und rauhigkeitsinduzierte Einflüsse berücksichtigt, die Polymermasse und vertikale und laterale Rauhigkeitsparameter bestimmt. Der Einfluss des Substituenten auf die Morphologie und das elektrochemische Verhalten in organischen Elektrolyten ist durch Vergleichsuntersuchungen an Poly(2,2?-bithiophen) illustriert. Die Sensormessungen erfolgten in wässrigen Modellelektrolyten mit unterschiedlich großen Anionen (LiClO4, NaClO4, NaNO3, Natriumtoluolsulfonat). Für die potentialabhängige Ionenaustauschreaktion konnte ein Einbau von Anionen bei der Oxidation des Polymers, der mit einem Ausstoß von Lösungsmittel verbunden war, nachgewiesen werden. Bei Reduktion des Polymers war der umgekehrte Vorgang zu beobachten. Kationen waren nicht nachweislich an den Austauschprozessen beteiligt. Als Sensorsignal wurde aus der bei Einbau der Ionen geflossenen Ladung und der reaktionsbedingten Masseänderung die ausgetauschte molare Masse und die inkorporierte Ionenmenge bestimmt. Die ausgetauschte molare Masse ergab für die unterschiedlichen Ionenspezies typische Werte, was eine Identifizierung der jeweiligen Analyten erlaubt. Die berechnete Analytmenge belegte eine erhöhte Empfindlichkeit für das in der Polymerisation verwendete Anion (Perchlorat) und eine geringe Empfindlichkeit für große Anionen (Toluolsulfonat) Für dünne, weniger poröse Filme war das Austauschverhältnis von Anion und Lösungsmittel annähernd proportional zu den Molekülgrößen der beteiligten Spezies. Ein zweiter Schwerpunkt der Arbeit war die Weiterentwicklung eines Verfahrens zur oxidativ?chemischen Abscheidung von Polythiophenfilmen unter Nutzung haftvermittelnder Substanzen. Dafür wurde die Filmqualität experimentell optimiert und Methoden zur strukturierten Abscheidung entwickelt. Zur Strukturierung der Polymerfilme wurden Methoden zur lokalen Aufbringung des Haftvermittlers auf Basis einer Maskierung des Substrates mit photostrukturierbaren Lackmasken bzw. auf Basis des Mikrokontaktdruckes der Haftvermittlerlösung entwickelt. Mit der Maskentechnik konnten Strukturen im Submikrometerbereich, mit dem Mikrokontaktdruck im Mikrometerbereich, erzielt werden. Der Nachweis der Sensitivität der chemisch polymerisierten Polythiophenfilme wurde für redoxaktive Gase mit Hilfe von Leitfähigkeitssensoren erbracht, und die Reaktionskinetik in Abhängigkeit von Feuchte und Temperatur untersucht.

Diverse conformational transitions and aggregations of regioregular head-to-tail polyhexylthiophene in different environments have been studied by means of AFM and UV-vis spectroscopy. A helical conformation of the main chain with 12 thiophenes rings per each helical turn has been proposed. Length of the particles varies from several nanometers to several hundreds nanometers and can be adjusted by the solvents composition or concentration of PATs. Such well-defined organic semiconductor 1D particles can be used as building blocks for future nanoscale and molecular level electronic devices. Oligothiophenes represent one of the most promising class of semiconductive materials for FET fabrication because of their good mobility and environmental stability. However, most of unsubstituted oligothiophenes are insoluble that suppresses their potential industrial utility. On the first stage of the work, conformation, crystalline structure, molecular packing and charge carrier mobility of the highly soluble regiochemically pure [Beta]-substituted sexithiophene were systematically studied. It was found that [Beta, Beta´]-DH6T possesses moderate PR-TRMC charge carrier mobility, but rather low field-effect mobility. The investigation showed that such a poor macroscopic electrical properties of [Beta, Beta´]-DH6T originate neither from the twist of the conjugated system nor from the crystalline disorder, but rather from low-dense crystalline packing and "wrong" molecular orientation. To overcome these obstacles two thiophene-based azomethines were designed to optimize a solubility, self-assembly, and a charge carrier mobility. The idea was to utilize the ability of the amide group to form strong hydrogen bonds in non-polar solvents and in solid state, but to be easily broken in presence of polar solvents. Thus, at the stage of a dissolution and a deposition, when the solubility is important, the hydrogen bonding can be "switched off" simply by addition of polar solvents and then, after the removal of polar additives, the self-assembly can be "switched on". It was found that incorporation of azomethine and amide moieties in the [Alpha, Omega]-position, and hexyl chains in [Beta]-position of quaterthiophene, indeed considerably improves the self-assembly properties without suppression of the solubility. Self-assembly of azomethine oligomers with (QT-amide) and without amide moieties (QT-aniline) were monitored by UV-vis, XRD, and AFM. It was found that QT-amide, processed from solution, forms highly ordered layered (terrace) structures. This aggregation mode is similar to the self-assembly of unsubstituted conjugated oligomers (such as pentacene) occurred upon their evaporation in vacuum. The sum of charge carrier mobilities (PR-TRMC data) for QT-aniline was shown to be below the detectable limit, but the mobility of QT-amide was determined to be 1.10-2 cm2 V-1 s-1. The later is comparable with the mobilities of the best organic semiconductors. All these significant differences in properties of related compounds can be attributed to the hydrogen bonding between QT-amide molecules responsible for the observed self-assembly.

This work deals with the sensor application of polythiophenes, which belong to the group of the conducting polymers. The first part focuses on sensor application of poly(3,4-ethylenedioxythiophene) (PEDOT) for ion detection in aqueous electrolytes. The advanced electrochemical quartz crystal microbalance was used for investigating the electrochemical polymerisation and the redox cycling behaviour of the polymer films deposited on the liquid facing electrode of the quartz. This method is based on impedance analysis of a piezoelectric quartz crystal. The deposited polymer mass and surface roughness parameters were estimated from the electrical impedance shift of the quartz during the polymerisation using a new calculation procedure for rough and viscoelastic films. The PEDOT data were compared with results from the electrochemical polymerisation of 2,2?-bithiophene to demonstrate the influence of the substituent on morphology and electrochemical properties in organic electrolytes. With regard to electrogravimetric sensor applications the ion exchange of the polymer in aqueous electrolytes (LiClO4, NaClO4, NaNO3, and sodium toluenesulfonate) during redox cycling was investigated. From the mass/charge balance the apparent exchanged molar mass and the absolute exchanged mass of ions were calculated. The mass balance indicated a transfer of anions and solvent during oxidation. No remarkable cation exchange in the reduction scan was observed. For all investigated electrolytes the calculated exchanged molar mass can be explained with a reversible replacement of solvent by anions during oxidation. The molar solvent/anion ratio was roughly proportional to the sizes of the species. The second part of the work describes investigations on gas sensing properties of polythiophene films prepared by a new preparation method. This two-step procedure is based on electroless polymerisation of conducting polymers. In the first step the substrate is coated with an adhesion promoter and in a second step the chemical surface polymerisation of the monomer is performed. This deposition method was combined with new patterning techniques. The basis of this process is the patterned application of the adhesion promoter which was realised either by a photoresist lacquer mask or by micro contact printing of the adhesion promoter solution. These methods provide patterning down to submicrometer scale. The sensing properties of the polythiophene films were demonstrated with chemiresistors for the redox active gases NO2 and NH3. The reaction kinetics were investigated depending on humidity and temperature. / Die Arbeit befasst sich mit der Untersuchung von Polythiophenen, einer Gruppe der intrinsisch leitfähigen Polymere, für die Anwendung als sensitive Filme in chemischen Sensoren. Ziel war es dabei, ausgewählte Aspekte des Sensoreinsatzes dieser Polymere zu beleuchten, um Wege zu einer verbesserten Sensorcharakteristik solcher Systeme aufzuzeigen. Der erste Teil der Ergebnisse konzentriert sich auf den Einsatz von Poly(3,4-ethylendioxythiophen) in Sensoren für die Bestimmung von Ionenkonzentrationen in wässrigen Medien. Die elektrochemische Polymerisation auf Schwingquarzen und der potentialinduzierte Ionenaustausch an solchen Polymerfilmen wurden mit Hilfe der elektrochemischen Quarzmikrowaage charakterisiert. Diese beruht auf der Impedanzanalyse von Schwingquarzen in der Nähe ihrer Resonanzfrequenz, was neben der Erfassung der Änderung der Resonanzfrequenz der Quarze auch die Untersuchung des Dämpfungsverhaltens und somit eine halbquantitative Analyse der mechanischen Eigenschaften des Polymerfilmes ermöglicht. Aus den Daten Impedanzanalyse während der Polymerisation wurden mit einem neuen Berechnungsmodells, das viskoelastische und rauhigkeitsinduzierte Einflüsse berücksichtigt, die Polymermasse und vertikale und laterale Rauhigkeitsparameter bestimmt. Der Einfluss des Substituenten auf die Morphologie und das elektrochemische Verhalten in organischen Elektrolyten ist durch Vergleichsuntersuchungen an Poly(2,2?-bithiophen) illustriert. Die Sensormessungen erfolgten in wässrigen Modellelektrolyten mit unterschiedlich großen Anionen (LiClO4, NaClO4, NaNO3, Natriumtoluolsulfonat). Für die potentialabhängige Ionenaustauschreaktion konnte ein Einbau von Anionen bei der Oxidation des Polymers, der mit einem Ausstoß von Lösungsmittel verbunden war, nachgewiesen werden. Bei Reduktion des Polymers war der umgekehrte Vorgang zu beobachten. Kationen waren nicht nachweislich an den Austauschprozessen beteiligt. Als Sensorsignal wurde aus der bei Einbau der Ionen geflossenen Ladung und der reaktionsbedingten Masseänderung die ausgetauschte molare Masse und die inkorporierte Ionenmenge bestimmt. Die ausgetauschte molare Masse ergab für die unterschiedlichen Ionenspezies typische Werte, was eine Identifizierung der jeweiligen Analyten erlaubt. Die berechnete Analytmenge belegte eine erhöhte Empfindlichkeit für das in der Polymerisation verwendete Anion (Perchlorat) und eine geringe Empfindlichkeit für große Anionen (Toluolsulfonat) Für dünne, weniger poröse Filme war das Austauschverhältnis von Anion und Lösungsmittel annähernd proportional zu den Molekülgrößen der beteiligten Spezies. Ein zweiter Schwerpunkt der Arbeit war die Weiterentwicklung eines Verfahrens zur oxidativ?chemischen Abscheidung von Polythiophenfilmen unter Nutzung haftvermittelnder Substanzen. Dafür wurde die Filmqualität experimentell optimiert und Methoden zur strukturierten Abscheidung entwickelt. Zur Strukturierung der Polymerfilme wurden Methoden zur lokalen Aufbringung des Haftvermittlers auf Basis einer Maskierung des Substrates mit photostrukturierbaren Lackmasken bzw. auf Basis des Mikrokontaktdruckes der Haftvermittlerlösung entwickelt. Mit der Maskentechnik konnten Strukturen im Submikrometerbereich, mit dem Mikrokontaktdruck im Mikrometerbereich, erzielt werden. Der Nachweis der Sensitivität der chemisch polymerisierten Polythiophenfilme wurde für redoxaktive Gase mit Hilfe von Leitfähigkeitssensoren erbracht, und die Reaktionskinetik in Abhängigkeit von Feuchte und Temperatur untersucht.