Dissertations / Theses: 'NANOCOMPOSITE AND PEDOT: PSS'

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Shen-Ming, Chen. "Applications of nanostructured materials and biomolecules for electrocatalysis and biosensors." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20454.

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Electronically conducting polymers are important materials, and composites of these materials with metal nanoparticles have also been drawn significant research attention in recent years. We prepared a highly stable Agnano-Poly (3, 4-ethylenedioxythiophene) (PEDOT) nanocomposite by one-pot synthesis method. Here, 3, 4-ethylenedioxythiophene (EDOT) is used as the reductant and polystyrene sulfonate (PSS-) as a dopant for PEDOT as well as particle stabilizer for silver nanoparticles (AgNPs). Agnano–PEDOT/PSS-nanocomposite was characterized by infrared (IR) spectroscopy, transmission electron microscopy (TEM). AgNPs are distributed uniformly around PEDOT polymer with an average particle size diameter of 10–15 nm and the nanocomposite film showed catalytic activity towards 4-nitro phenol. Some types of including Ag bimetallic nanoparticles and nanostructured materials could be directly applied for the electroanalysis and biosensing applications. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20454

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CHAKMA, SHIMUL. "FABRICATION AND CHARACTERIZATION OF CEO2/RGO CONDUCTING ELECTRODES." Thesis, DELHI TECHNOLOGICAL UNIVERSITY, 2021. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18425.

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Fabrication of advanced electrode material is highly desired for novel electrochemical sensor development. In this work, cerium oxide (CeO2) nanoparticles were successfully loaded on reduced graphene oxide (RGO) by one-step hydrothermal synthesis approach, and this nanocomposite (CeO2/ rGO) was used as novel electrode material for urea detection. Herein, efforts have been made to fabricate a conducting paper based sensor comprising of CeO2/rGO nanocomposite and PEDOT: PSS. The conductivity of the PEDOT: PSS coated paper significantly increases from 6.9 x 10-5 S/cm to 1.1 x 10-4 S/cm on treatment with ethylene glycol. Further, the modification of conducting paper with synthesized CeO2/rGO nanocomposite shows better electrochemical properties.

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Yao, Xiao. "Grayscale patterning of PEDOT: PSS films by multi-photon lithography." Thesis, Kansas State University, 2008. http://hdl.handle.net/2097/780.

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Master of Science
Department of Chemistry
Daniel A. Higgins
Lithography techniques have been widely used to fabricate optical, electronic and optoelectronic devices with sub-micron scale spatial resolution. In the most common lithographic procedures, a light sensitive polymer, called a photoresist, is exposed and developed to form a binary relief pattern on a substrate. The finest features are produced by X-ray or electron-beam methods, both of which are very expensive to employ. Less expensive methods use ultraviolet (UV) light to expose the photoresist through a photomask. The resolution in these methods is somewhat lower and is governed by diffraction of light by the photomask, the quality of the photomask, and by any chemical/physical development steps subsequently employed. Due to the above limitations, we have been investigating direct-write, ablative multiphoton lithography as an alternative method for preparing high-resolution patterns. With this method, near-IR light from an ultrafast pulsed laser source is focused into a polymer film, leading to depolymerization and vaporization of the polymer. Arbitrary binary patterns can be produced by raster scanning the sample while controlling exposure of the film to the laser. Importantly, high-resolution etching of the polymer film is achieved without the use of a photomask and without chemical development steps. While arbitrary patters are easily prepared, it is also possible to prepare three-dimensional (i.e. grayscale) surface relief structures. In this study, ablative multiphoton photolithography is used to prepare binary and grayscale structures in thin films of PEDOT:PSS, an electrically conductive organic polymer blend. A simple kinetic model is proposed to explain the etching process. Data on the power-dependence of polymer etching can be fit to this model and is used to determine the order of the nonlinear optical process involved. The etch depth as a function of laser focus is also investigated and shown to follow the same kinetic model. The results show that three-dimensional (grayscale) patterns can be prepared by modulating either the laser power or the laser focus. Images of several binary and grayscale structures prepared by this method are presented.

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Vichessi, Raquel Braz. "Propriedades interfaciais de eletrodos modificados pedot : PSS/AU NPs aplicados na eletrocatálise de nitrofenóis." reponame:Repositório Institucional da UFPR, 2015. http://hdl.handle.net/1884/46323.

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Orientador : Prof. Dr. Marcio Vidotti
Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Exatas, Programa de Pós-Graduação em Química. Defesa: Curitiba, 22/04/2015
Inclui referências : f. 92-103
Área de concentração
Resumo: A modificação de eletrodos de ITO foi realizada a partir da eletropolimerização do PEDOT:PSS utilizando dois distintos regimes eletroquímicos: potenciostático e potenciodinâmico. Em seguida, a partir de um método simples de imersão em sal de ouro e aplicação de potencial, foram obtidas nanopartículas de ouro na superfície polimérica. A caracterização da morfologia nodular polimérica foi realizada pelas técnicas de microscopia eletrônica de varredura (MEV) e microscopia de força atômica (AFM), sendo observadas diferentes homogeneidades nas superfícies poliméricas e também a presença de poros nos eletrodos modificados por meio do crescimento potenciodinâmico. Os resultados de espectroscopia RAMAN e e espectroscopia de impedância eletroquímica (EIS) confirmam a presença de nanopartículas e permitiram a correlação das propriedades superficiais dos eletrodos com os valores de transferência eletrônica. Estudos de redução eletroquímica de três isômeros de nitrofenóis (orto-, meta- e para-nitrofenol) mostram o efeito eletrocatalítico dos eletrodos modificados. Os resultados obtidos apresentam a relação das propriedades interfaciais eletrodo-nitrofenol, sendo caracterizados por medidas de ângulo de contato e espectroscopia RAMAN. Palavras-chave: eletrodos modificados, PEDOT:PSS/Au NPs, eletrocatálise, nitrofenóis, propriedades interfaciais.
Abstract: The modification of ITO electrodes was performed by electropolymerization of PEDOT:PSS through two distinct electrochemical regimes: potentiostatic and potenciodynamic. After modification using, a simple method of gold salt immersion and potential application, gold nanoparticles were obtained on the polymeric surface. The characterization of nodular morphology was made using scanning electronic microscopy (SEM) and atomic force microscopy (AFM). Different surface homogeneity and porous presence were observed due to potenciodynamic growth. The results from RAMAN spectroscopy and electrochemical impedance spectroscopy (EIS) confirm the presence of the nanoparticles and allow the correlation between surface properties and electronic transfer values of the electrodes. Electrochemical reduction studies of three nitrophenol isomers (orto-, meta- and para-) show the electrocatalytic effect of the modified electrodes. The obtained results demonstrate the relation of electrode-nitrophenol interface properties, being characterized by angle contact measurements and RAMAN spectroscopy. Keywords: modified electrodes, PEDOT:PSS/Au NPs, electrocatalysis, nitrophenol, interface properties.

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Garnier, Jérôme. "Polymer electrochromism and surface plasmons combined on metallic diffraction gratings." Thesis, Linköping University, Department of Science and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11522.

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All conducting polymers are potentially electrochromic, owing to the injection of charge carriers that changes their electronic structure and results in a shift of their optical absorption towards higher wavelengths. PEDOT-PSS and PEDOT-S are very promising materials in terms of electrochromic properties, due to the good contrast existing between their doped and undoped forms. However this contrast has to be enhanced in order to design more efficient electrochromic devices, and new solutions should thus be found in order to solve this issue.

Surface plasmons are described as electromagnetic waves propagating along the surface between a dielectric and a metal. Coupled to an incident radiation, they create an energy loss in the light transmitted and reflected by the interface. When the metallic surface is periodically corrugated, this absorption phenomenon due to plasmonic resonance occurs at a specific wavelength that depends on several parameters, such as the incidence angle, the dielectric constants of the two media and the grating period. By coating metallic gratings with electrochromic polymers, we may thus be able to trigger a plasmonic absorption at a given wavelength and shift it upon reduction or oxidation of the material.

Electrochromic devices consisting of PEDOT-PSS or PEDOT-S spin-deposited on gold and silver gratings were investigated by UV-visible reflectance measurements. The periodically corrugated structures were reproduced from commercial gratings by soft nanolithography and were analyzed by AFM. Some electrochromic cells exhibited new colors or a high shift of the plasmonic resonance upon redox switching of the polymer film. Depending on the step and the nature of the grating employed, this shift could reach 20 nm in the case of PEDOT-PSS and more than 100 nm for PEDOT-S. A theoretical model was found to predict the wavelength of plasmonic excitation and the orientation of the shift.

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Oziat, Julie. "Electrode 3D de PEDOT : PSS pour la détection de métabolites électrochimiquement actifs de Pseudomonas aeruginosa." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEM026/document.

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Lors d’infections, l'identification rapide des micro-organismes est cruciale pour améliorer la prise en charge du patient et mieux contrôler l'usage des antibiotiques. L’électrochimie présente plusieurs avantages pour les tests rapides : elle permet des analyses in situ, faciles et peu chères dans la plupart des liquides. Son utilisation pour l’identification bactérienne est récente et provient de la découverte de molécules donnant de forts signaux redox dans le surnageant de bactéries du genre Pseudomonas.Cette thèse s’intéresse à l’analyse de surnageants de la bactérie Pseudomonas aeruginosa, 4e cause de maladies nosocomiales en Europe. Tout d’abord, l’intérêt de l’analyse électrochimique de surnageants de culture dans une visée d’identification a été évalué. Pour cela, après l’étude de 4 potentiels biomarqueurs de la présence de cette bactérie en solutions modèles, l’analyse électrochimiques de surnageant de plusieurs souches P. aeruginosa a été effectuée. Les résultats obtenus sont prometteurs. Ils mettent en évidence une signature électrochimique complexe et souche-dépendante du surnageant.La suite de la thèse s’est intéressée à l’amplification de la détection électrochimique grâce à l’utilisation du polymère conducteur PEDOT:PSS. Il a été choisi pour ses bonnes propriétés électrochimiques, sa biocompatibilité et sa facilité de mise en forme. Il a tout d’abord été utilisé sous forme de films minces pour confirmer son pouvoir d’amplification. Une électrode 3D a ensuite été fabriquée par lyophilisation. L’utilisation de ce type d’électrode permet d’amplifier encore la détection en augmentant la surface d’échange mais aussi en confinant les bactéries dans l'électrode
During infections, microorganisms fast identification is critical to improve patient treatment and to better manage antibiotics use. Electrochemistry exhibits several advantages for rapid diagnostic: it enables easy, cheap and in situ analysis in most liquids. Its use for bacterial identification is recent and comes from the discovery of molecules giving strong redox signals in the bacterial supernatant of the Pseudomonas genus.This thesis focuses on the supernatants analysis of the bacterium Pseudomonas aeruginosa. This bacteria is the fourth cause of nosocomial infections in Europe. First, the interest of supernatants electrochemical analysis for identification was evaluated. For this, after the study of four redox biomarkers of this bacterium in model solutions, supernatant electrochemical analysis of several strains of P. aeruginosa was performed. The results are promising. They highlight a complex strain-dependant electrochemical signature of the supernatant.Following, we focused in the amplification of the electrochemical detection through the use of the conductive polymer PEDOT: PSS. This polymer was chosen for its good electrochemical properties, its biocompatibility and its easy shaping. It was first used as a thin films to confirm its amplification power through biomarker adsorption. Then, a 3D electrode was made by freeze drying. The use of this type of electrode can further amplify the detection by increasing the exchange surface as well as confining the bacteria in the electrode

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Almeida, Tiago Pedroso de. "Estudo da aplicação de filmes automontados de PAH/PEDOT: PSS em membranas de Nafion®." Universidade Federal de São Carlos, 2013. https://repositorio.ufscar.br/handle/ufscar/8351.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
The present work aimed the fabrication of layer-by-layer nanostructured films of poly (allylaminehydrochloride) (PAH) and poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) onto Nafion® 212 membranes. Nafion® is the most used polyelectrolyte in proton exchange membranes (PEM) fuel cells due to its high proton conduction and good chemical stability at ambient temperature. Therefore, this polyelectrolyte presents some disadvantages due to the high methanol permeability when applied in Direct Methanol Fuel Cells (DMFC), reducing drastically the performance of the device. We studied how ultrathin films of PAH/PEDOT:PSS influence the methanol permeability and proton conduction in the LbL modified membranes. Results indicated good adherence of the LbL films onto Nafion® 212 and also good action as a methanol barrier. Nonetheless, together with the methanol blocking there was also a reduction in the proton conductivity, which occurs due to the LbL dipping deposition on both sides of Nafion® 212, trapping water inside the Nafion membrane, and certainly affecting the proton conduction. Moreover, the LbL film deposition might use some important chemical groups present at the Nafion® surface, used to water permeation, also affecting the proton permeation throughout the membrane.
O presente trabalho visou a fabricação de filmes automontados nanoestruturados (LbL, do inglês layer-by-layer) de poli(alilaminahidroclorada) (PAH) e poli(3,4-etilenodioxitiofeno)poli(estirenossulfado)(PEDOT:PSS) sobre membranas de Nafion® 212. O Nafion® é o polieletrólito mais usado em células combustíveis do tipo PEM (do inglês Proton Exchange Membrane) devido a sua alta capacidade de condução protônica e boa estabilidade química em temperatura ambiente. Entretanto, este polieletrólito apresenta a desvantagem da alta permeação de metanol quando aplicado em células combustíveis a base de metanol direto (DMFC, do inglês Direct Methanol Fuel Cell), que reduz drasticamente o desempenho do dispositivo. Estudamos como filmes ultrafinos de PAH/PEDOT:PSS influenciam a permeabilidade do metanol e a condução protônica de membranas de Nafion® modificadas com filme LbL. Os resultados indicaram boa aderência dos filmes nanoestruturados sobre o Nafion® 212, e ainda boa atuação como barreira à passagem de metanol. No entanto, junto com o bloqueio à passagem de metanol houve redução na condução protônica, que ocorre pelo fato da técnica LbL por imersão depositar material em ambos os lados no Nafion® 212, aprisionando a água no interior da membrana, que certamente afeta a condução protônica. Adicionalmente, a deposição do filme LbL pode estar usando alguns agrupamentos químicos importantes na superfície do Nafion®, utilizados para permeação de água, também afetando a condução protônica através da membrana.

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Chivers, Benjamin William. "Development of Novel PEDOT:PSS Fabrication Techniques for High Performance, Flexible RFID Antennas and Energy Storage Devices." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20155.

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Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) has been widely studied as either nanometre-scale, transparent films or a conductive, capacitive composite material in electronic devices. While significant effort has been directed towards increasing PEDOT:PSS conductivity in transparent films, very little nanoscale, morphological consideration has been applied to micron-scale PEDOT:PSS materials. As a result, PEDOT:PSS conductivity often decreases in micron-scale materials, and the polymer has been largely overlooked as a high performance material in practical applications. In this thesis, PEDOT:PSS fabrication techniques are optimised to produce high conductivity and high electrochemical performance micron-scale quantities of PEDOT:PSS. The optimised PEDOT:PSS is used to fabricate an RFID antenna with extraordinary radiation efficiency, a high efficiency zinc/bromine flow battery anode, and an ultra-high performance composite-fibre-supercapacitor. A novel fabrication technique was developed to maintain PEDOT:PSS electrical and electrochemical performance in micron-scale applications. By submersion in ethylene glycol, PEDOT:PSS phase separation, conformational changes, stability and PEDOT loading were optimised for a commercially available PEDOT:PSS. Polymer films 40 m thick were reliably produced with over 500 S cm-1. The high performance PEDOT:PSS was fabricated into a 2.45 GHz RFID dipole antenna, achieving 99.7% peak radiation efficiency, a novel result for a non-metal antenna. The same morphologically considerate approach was applied to zinc/bromine flow battery anode design, more than doubling peak charge density. Energy density increased by over 50%, and charge efficiency increased by 9.3%, directly increasing battery efficiency. PEDOT:PSS was composited with reduced graphene oxide to produce a symmetric fibre supercapacitor with very high capacitance, 138 F cm-3 compared to 55 F cm-3 and 14 F cm-3 for PEDOT:PSS and rGO respectively.

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GALLIANI, DANIELA. "Poly(3,4-ethylendioxythiophene) based materials for thermoelectric applications." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2018. http://hdl.handle.net/10281/199131.

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I polimeri intrinsecamente conduttori sono una classe di materiali con caratteristiche uniche. In quanto materiali polimerici sono leggeri e flessibili, possono essere facilmente processati e stampati. Al contempo, però, possono condurre corrente elettrica, raggiungendo anche conducibilità metalliche. Questa combinazione eccezionale ha consentito lo sviluppo di dispositivi elettronici stampati e flessibili, i quali risultano interessanti nell’ambito dei dispositivi portabili, sia integrati nel corpo umano sia indossabili. L’applicazione termoelettrica di questi polimeri conduttori ha recentemente guadagnato rilievo in campo scientifico. Un dispositivo termoelettrico (organico) può convertire il calore in energia elettrica grazie all’effetto Seebeck. Il dispositivo può così recuperare il calore di scarto dissipato in tutti i processi che coinvolgono il consumo di energia e trasformarlo in energia utilizzabile. Anche se i polimeri conduttori hanno già mostrato interessanti proprietà termoelettriche, il loro utilizzo in questo campo è ancora molto limitato per via delle basse efficienze di conversione termoelettrica raggiunte finora, che impediscono a questi materiali di essere competitivi con i più diffusi materiali inorganici per questa applicazione, ovvero i tellururi. Il design di un polimero conduttore che abbia elevate prestazioni termoelettriche parte necessariamente da una conoscenza approfondita di quali tecniche e trattamenti influenzino le proprietà finali di trasporto di carica. La complessità intrinseca di questi sistemi, tuttavia, rende spesso difficoltoso ottenere queste informazioni, impedendo la comprensione di fenomeni coinvolti. Questo progetto di dottorato ha riguardato lo studio dell’impatto di diversi parametri sulle proprietà termoelettriche dei polimeri conduttori, con lo scopo di raggiungere una comprensione approfondita di come il trasporto di carica ne venga influenzato. Nello specifico, lo studio ha riguardato il poli(3,4-etilendiossitiofene) -PEDOT-, il quale è stato studiato modificando diversi parametri a tre livelli di perturbazione del sistema. In primo luogo, un’indagine è stata svolta sul ruolo delle condizioni di polimerizzazione e su quello dei trattamenti effettuati dopo la polimerizzazione. In particolare, è stata studiata l’influenza di diverse tecniche di polimerizzazione, diversi ossidanti e diversi solventi sulla vi qualità finale del film polimerico. Inoltre, il livello di ossidazione del PEDOT è stato modificato dopo la polimerizzazione, ottenendo un’ottimizzazione dell’efficienza termoelettrica. Ad un secondo livello di perturbazione, la struttura molecolare del monomero è stata modificata per preparare un copolimero. Il copolimero includeva una porzione centrale coniugata (e quindi, conduttiva) e due porzioni laterali non coniugate (isolanti), che hanno comportato una modifica sostanziale delle proprietà di trasporto del materiale finale. I risultati ottenuti sulla nuova struttura mostrano la versatilità di questa strategia e come le proprietà di trasporto possano essere finemente modificate grazie all’introduzione di modifiche della struttura molecolare. Infine, al terzo livello, le proprietà macroscopiche del PEDOT sono state modificate grazie all’introduzione di nanostrutture di natura inorganica. Questa strategia è solitamente utilizzata per migliorare l’efficienza termoelettrica dei materiali inorganici, grazie agli effetti benefici dovuti alla nanostrutturazione. Due tipologie diverse di nanoparticelle di ossidi metallici (CuO e Mn3O4) sono state sintetizzate in diverse forme e dimensioni e introdotte nella matrice di PEDOT in diverse concentrazioni. Grazie allo studio dell’effetto dell’umidità sulle proprietà di trasporto ed allo studio sulla variazione dello stato di ossidazione è stato possibile ottenere nuove informazioni sul comportamento elettrico dei nanocompositi.
Intrinsically conductive polymers (ICPs) are a class of organic materials characterized by unique features. They are lightweight, flexible and easy to process and print, as expected from polymers, but, also, they can conduct electricity up to metallic conductivities. Such an exceptional pairing of characteristics enables the development of flexible and printed electronic devices, which are of a particularly appealing for portable electronic devices, even integrated in the human body (e.g. implantable biosensors) or worn (e.g. smartwatches). Even thermoelectric (TE) application of ICPs recently gained a lot of attention. An organic TE generator (OTEG) can convert heat into electrical energy by means of the Seebeck effect. This technology aims to recover heat produced as low-grade side-product of energy consumption and to transform it into exploitable energy. Even though ICPs showed promising TE properties, their use is still hindered by low TE efficiencies, which cannot compete with the inorganic benchmark (i.e. tellurides). The design of better ICPs for TE application must start from a deep knowledge of which techniques and treatments impact the charge transport features. The intrinsic complexity of ICP systems, however, often makes this task difficult, preventing a full comprehension of the phenomena involved. This PhD project focused on the impact of different parameters on TE properties of ICPs, aiming at the needed deeper understanding on how charge transport is affected. The specific ICP poly(3,4-ethylendioxythiophene) -PEDOT- was investigated modifying different parameters at three different levels of system perturbation. First, the role of polymerization conditions and post-polymerization treatments was studied. Different polymerization techniques, oxidants and solvents have been used for the same ICP, and the occurring changes have been investigated. Moreover, PEDOT oxidation level was tuned to optimize TE efficiency. At a second level, the monomer molecular structure was modified to prepare a PEDOT-based copolymer. The copolymer included conjugated (i.e. conductive) and not conjugated (i.e. not conductive) portions, which deeply impacted the charge transport behaviour. The results show the versatility of this strategy, still barely explored in TE field, and how final transport properties can be finely tuned by means of molecular modifications. Finally, at a third level, PEDOT macroscopic features were tuned by embedding inorganic nanostructure. Such a strategy is usually exploited to improve TE efficiency by means of nanostructuration beneficial effects already known in inorganic materials. Nanoparticles of two different metal oxides (CuO and Mn3O4) of different size and shape were dispersed in PEDOT matrix. Evaluation of humidity and oxidation level effects on charge transport features allowed to obtain novel insights into transport properties in nanocomposites.

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Cao, Zhixiong. "Silver nanoprisms in plasmonic organic solar cells." Thesis, Ecole centrale de Marseille, 2014. http://www.theses.fr/2014ECDM0015/document.

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On constate une forte demande mondiale d' énergie propre et renouvelable en raison de la consommation rapide des combustibles fossiles non renouvelables et l'effet de serre qui en résulte. Une solution prometteuse pour produire une énergie propre et renouvelable est d'utiliser des cellules solaires pour convertir l' énergie solaire directement en électricité. Comparativement à leurs homologues inorganiques, les cellules solaires organiques (OSCs) sont maintenant intensivement étudiées en raison des avantages tels que le poids léger, la flexibilité, la compatibilité avec les procédés de fabrication à faibles coûts. Malgré ces avantages, l'efficacité de conversion (PCE) des OSCs doit encore être améliorée pour la commercialisation à grande échelle. Les cellules solaires organiques sont réalisées en pile de couches minces comprenant des électrodes, la couche de transport d' électrons, la couche de polymère actif et la couche de transport de trous. Dans cette étude, nous sommes concernés par la couche de PEDOT:PSS qui est couramment utilisée comme une couche tampon entre l'électrode anodique et la couche de polymère actif de cellules solaires organiques. Cette étude vise à intégrer différentes concentrations de nanoprismes (NPSMs) d'argent de taille sub-longueur d'onde dans du PEDOT: PSS afin de profiter de leurs propriétés optiques uniques nées de résonances de plasmons de surface localisées (LSPR) pour améliorer la collecte lumineuse et l'efficacité de génération de charge en optimisant l' absorption et la diffusion de la lumière. Nous avons constaté que les facteurs clés qui contrôlent les performances des cellules solaires plasmoniques comprennent non seulement les propriétés optiques, mais également les propriétés structurelles et électriques des couches hybrides de PEDOT:PSS comprenant des NPSMs d' Ag. D'une part, l'ajout de NPSMs d' Ag conduit ¨¤ (1) une augmentation de l'absorption optique; (2) de la diffusion de la lumière ¨¤ de grands angles ce qui pourrait conduire ¨¤ un meilleur piégeage de la lumière dans les OSCs. D'autre part, (1) la rugosité de surface est augment¨¦e en raison de la formation d'agglomérats de NPSMs d' Ag, ce qui conduit ¨¤ une meilleure efficacité de collecte de charge; (2) la résistance globale des films hybrides est également augment¨¦e en raison de l'excès de PSS introduit par les NPSMs d' Ag incomplètement purifiées, inférieur courant de court-circuit (Jsc) qui en résulte; (3) les Ag NPSMs et leurs agglomérats ¨¤ l'interface PEDOT:PSS/couche photo-active pourraient agir comme des centres de recombinaison, conduisant ¨¤ une réduction de la résistance de shunt, du Jsc et de la tension en circuit ouvert (Voc). Afin de résoudre partiellement l'inconvénient (2) et (3), en intégrant des NPSMs d¡¯Ag davantage purifiés et une petite quantité de glycérol dans le PEDOT:PSS, la résistance des couches hybrides de PEDOT:PSS-Ag-NPSMs peut ¨être réduite à une valeur comparable ou inférieure ¨¤ celles couches vierges. Les futurs progrès en chimie de surface colloïdale et l'optimisation sur le processus d'incorporation des nanoparticules seront nécessaires pour produire des cellules solaires organiques plasmoniques de meilleures performances
Nowadays there has been a strong global demand for renewable and clean energy due to the rapid consumption of non-renewable fossil fuels and the resulting greenhouse effect. One promising solution to harvest clean and renewable energy is to utilize solar cells to convert the energy of sunlight directly into electricity. Compared to their inorganic counterparts, organic solar cells (OSCs) are now of intensive research interest due to advantages such as light weight, flexibility, the compatibility to low-cost manufacturing processes. Despite these advantages, the power conversion efficiency (PCE) of OSCs still has to be improved for large-scale commercialization. OSCs are made of thin film stacks comprising electrodes, electron transporting layer, active polymer layer and hole transporting layer. In this study, we are concerned with PEDOT:PSS layer which is commonly used as a buffer layer between the anodic electrode and the organic photoactive layer of the OSC thin film stack. We incorporated different concentrations of silver nanoprisms (NPSMs) of sub-wavelength dimension into PEDOT:PSS. The purpose is to take advantage of the unique optical properties of Ag MPSMs arisen from localized surface plasmon resonance (LSPR) to enhance the light harvest and the charge generation efficiency by optimizing absorption and scattering of light in OSCs. We found that the key factors controlling the device performance of plasmonic solar cells include not only the optical properties but also the structural and electrical properties of the resulting hybrid PEDOT:PSS-Ag-NPSM-films. On one hand, the addition of Ag NPSMs led to (1) an increased optical absorption; (2) light scattering at high angles which could possibly lead to more efficient light harvest in OSCs. On the other hand, the following results have been found in the hybrid films: (1) the surface roughness was found to be increased due to the formation of Ag agglomerates, leading to increased charge collection efficiency; (2) the global sheet resistance of the hybrid films also increases due to the excess poly(sodium styrenesulphonate) introduced by incompletely purified Ag NPSMs, resulting in lower short circuit current (Jsc); (3) the Ag nanoprisms and their agglomerates at the PEDOT:PSS/photoactive layer interface could act as recombination centers, leading to reductions in shunt resistance, Jsc and open circuit voltage (Voc). In order to partially counteract the disadvantage (2) and (3), by incorporating further purified Ag NPSMs and/or a small amount of glycerol into PEDOT:PSS, the sheet resistance of hybrid PEDOT:PSS-Ag-NPSM-films was reduced to a resistance value comparable to or lower than that of pristine film

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Carr, Olivia [UNESP]. "Caracterização e aplicação da Blenda PEDOT : PSS/PVA na construção de eletrodos transparentes e dispositivos eletroluminescentes." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/123746.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Desde a descoberta das propriedades eletrônicas de materiais poliméricos orgânicos sintéticos, várias pesquisas foram feitas a fim de desenvolver dispositivos eletrônicos e optoeletrônicos, como transistores de efeito de campo, diodos emissores de luz, células eletroquímicas emissoras de luz, células solares e sensores. A motivação para essas pesquisas tem sido algumas características específicas dos materiais orgânicos como a flexibilidade, dispositivos de espessura ultra-finos, baixo custo e fácil processamento. Este trabalho teve como objetivo estudar e caracterizar a blenda polimérica formada pelo polímero condutor Poli(3,4-etilenodioxitiofeno):Poli(estirenosulfonado) (PEDOT:PSS) e o polímero isolante Poli(álcool vinílico) (PVA). As amostras foram caracterizadas por técnicas espectroscópicas (UV-Vis), morfológicas (AFM) e medidas elétricas AC e DC. A blenda (PEDOT:PSS/PVA) composta por (40/60), respectivamente, apresentou um material percolado, na qual a condutividade cresce linearmente com a concentração do polímero condutor. Os resultados mostraram que o transporte de carga nas blendas pode ser bem descrito pelo modelo Variable Range Hopping (VRH-3D). Amostras com concentrações inferiores a 10% em massa de PEDOT:PSS na blenda apresentaram separação de fase entre os polímeros constituintes, levando a dois processos de condução elétrica distintos, um predominante através da matriz isolante (PVA) e outro através de ilhas constituídas pelo polímero condutor (PEDOT:PSS). Da caracterização óptica da blenda, para aplicações como eletrodo transparente, obteve-se filmes com alta condutividade elétrica e baixo coeficiente de absorção óptico, para concentrações próximas a 30% de PEDOT:PSS. A composição da blenda (PEDOT:PSS/PVA) com as micro partículas de Zn2SiO4:Mn, para aplicação em dispositivos EL, resultou em dispositivos emissores de luz com pico de emissão em 530 nm e pureza de cor de 88%
Since the discovery of the electronic properties of synthetic organic polymeric materials, several studies have been made to develop electronic and opto-electronics devices such as field effect transistors, light emitting diodes, light emitting electrochemical cells, solar cells and sensors. The motivation for this research was some specific features of organic materials such as flexibility, ultra-thin thickness, low cost and easy processing for application as transparent electrode in organic devices. This work aimed to study and characterize the polymer blend formed by the conductive polymer poly (3,4-ethylenedioxythiophene): poly (estirenosulfonado) (PEDOT:PSS) and the insulating polymer poly (vinyl alcohol) (PVA). The samples were characterized by spectroscopic techniques (UV-Vis), morphological (AFM) and electrical measurements AC and DC. The blend (PEDOT:PSS/PVA) containing (40/60), respectively, resulted in a percolated material, wherein the conductivity increases linearly with the concentration of conductive polymer. The results showed that the charge transport in the blends can be well described by the Variable Range Hopping (VRH-3D) model. Samples with concentrations below 10% by weight of PEDOT:PSS in the blend showed phase separation of the constituent polymers, resulting in two distinct electrical conduction processes, a predominant via the insulating matrix (PVA) and a second via islands formed by the polymer conductor (PEDOT:PSS). Optical characterization of the blend, for applications as transparent electrode, reveals that high electrical conductivity and low coefficient of optical absorption is obtained for concentrations close to 30% of PEDOT:PSS. The composition of the blend (PEDOT:PSS/PVA) with micro particles of Zn2SiO4:Mn, results in light emitting devices with emission peak at 530 nm and color purity of 88%
FAPESP: 2012/01624-5

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Carr, Olivia. "Caracterização e aplicação da Blenda PEDOT : PSS/PVA na construção de eletrodos transparentes e dispositivos eletroluminescentes /." Rio Claro, 2015. http://hdl.handle.net/11449/123746.

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Orientador: Dantes Luis Chinaglia
Banca: Neri Alves
Banca: José Antonio Malmonge
Resumo: Desde a descoberta das propriedades eletrônicas de materiais poliméricos orgânicos sintéticos, várias pesquisas foram feitas a fim de desenvolver dispositivos eletrônicos e optoeletrônicos, como transistores de efeito de campo, diodos emissores de luz, células eletroquímicas emissoras de luz, células solares e sensores. A motivação para essas pesquisas tem sido algumas características específicas dos materiais orgânicos como a flexibilidade, dispositivos de espessura ultra-finos, baixo custo e fácil processamento. Este trabalho teve como objetivo estudar e caracterizar a blenda polimérica formada pelo polímero condutor Poli(3,4-etilenodioxitiofeno):Poli(estirenosulfonado) (PEDOT:PSS) e o polímero isolante Poli(álcool vinílico) (PVA). As amostras foram caracterizadas por técnicas espectroscópicas (UV-Vis), morfológicas (AFM) e medidas elétricas AC e DC. A blenda (PEDOT:PSS/PVA) composta por (40/60), respectivamente, apresentou um material percolado, na qual a condutividade cresce linearmente com a concentração do polímero condutor. Os resultados mostraram que o transporte de carga nas blendas pode ser bem descrito pelo modelo Variable Range Hopping (VRH-3D). Amostras com concentrações inferiores a 10% em massa de PEDOT:PSS na blenda apresentaram separação de fase entre os polímeros constituintes, levando a dois processos de condução elétrica distintos, um predominante através da matriz isolante (PVA) e outro através de ilhas constituídas pelo polímero condutor (PEDOT:PSS). Da caracterização óptica da blenda, para aplicações como eletrodo transparente, obteve-se filmes com alta condutividade elétrica e baixo coeficiente de absorção óptico, para concentrações próximas a 30% de PEDOT:PSS. A composição da blenda (PEDOT:PSS/PVA) com as micro partículas de Zn2SiO4:Mn, para aplicação em dispositivos EL, resultou em dispositivos emissores de luz com pico de emissão em 530 nm e pureza de cor de 88%
Abstract: Since the discovery of the electronic properties of synthetic organic polymeric materials, several studies have been made to develop electronic and opto-electronics devices such as field effect transistors, light emitting diodes, light emitting electrochemical cells, solar cells and sensors. The motivation for this research was some specific features of organic materials such as flexibility, ultra-thin thickness, low cost and easy processing for application as transparent electrode in organic devices. This work aimed to study and characterize the polymer blend formed by the conductive polymer poly (3,4-ethylenedioxythiophene): poly (estirenosulfonado) (PEDOT:PSS) and the insulating polymer poly (vinyl alcohol) (PVA). The samples were characterized by spectroscopic techniques (UV-Vis), morphological (AFM) and electrical measurements AC and DC. The blend (PEDOT:PSS/PVA) containing (40/60), respectively, resulted in a percolated material, wherein the conductivity increases linearly with the concentration of conductive polymer. The results showed that the charge transport in the blends can be well described by the Variable Range Hopping (VRH-3D) model. Samples with concentrations below 10% by weight of PEDOT:PSS in the blend showed phase separation of the constituent polymers, resulting in two distinct electrical conduction processes, a predominant via the insulating matrix (PVA) and a second via islands formed by the polymer conductor (PEDOT:PSS). Optical characterization of the blend, for applications as transparent electrode, reveals that high electrical conductivity and low coefficient of optical absorption is obtained for concentrations close to 30% of PEDOT:PSS. The composition of the blend (PEDOT:PSS/PVA) with micro particles of Zn2SiO4:Mn, results in light emitting devices with emission peak at 530 nm and color purity of 88%
Mestre

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Simaite, Aiva. "Development of ionic electroactive actuators with improved interfacial adhesion : towards the fabrication of inkjet printable artificial muscles." Thesis, Toulouse, INSA, 2015. http://www.theses.fr/2015ISAT0043/document.

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Les actionneurs à base de polymères électroactifs ioniques constituent une alternative prometteuse par rapport aux actionneurs conventionnels, en particulier lorsqu’une réponse comparable à celle d’un muscle naturel est recherché. Parmi eux, les actionneurs à base de polymères conducteurs constituent une voie prometteuse pour des applications biomédicale où la biocompatibilité, la compacité et un positionnement précis sont requis. Néanmoins, l’essor de dispositifs fonctionnels est fortement ralenti en raison de la faible efficacité d’actionnement et de la rapide dégradation des performances de ce type d’actionneurs. L’absence de rétroaction sur la force ou sur la position est également un autre aspect limitant le développement de cette approche. L’objectif de cette thèse est de proposer une technique de fabrication à grande échelle pour l’élaboration d’actionneurs à base de polymères électroactifs ioniques et permettant également l’intégration de capteurs pour un contrôle rétroactif. L’impression par jet d’encre est une technologie clé pour le dépôt de polymères et une des plus alternatives les plus prometteuses pour la production d’actionneurs à base de polymères conducteurs. Cependant, la fabrication d’actionneurs par technique jet d’encre n’est pas encore totalement maîtrisée à cause des propriétés rhéologiques des solutions de polymères conducteurs qui rendent difficile le contrôle de l’éjection de gouttes mais également en raison de la nature complexe des interactions entre la solution et l’échantillon qui peut conduire à une faible adhésion et un mauvais contrôle de l’infiltration de l’encre. Pour optimiser cette méthode de fabrication, des membranes hybrides contenant des ions ont été développées. Le greffage d’un monomère hydrophile par plasma argon avec un dépôt contrôlé en profondeur a été utilisé pour obtenir des membranes en polyfluorure de vinylidène (PVDF) avec des surfaces hydrophiles tout en conservant une zone centrale hydrophobe. Ces membranes hybrides ont permis d’obtenir, par dépôt de gouttes, des actionneurs de morphologies très variées à base de polymères conducteurs. En outre, la durée de vie d’actionneurs obtenus avec une solution conductrice de poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) a été sensiblement augmentée avec des déformations de plus de 0.6% sans qu’aucun signe de délamination ne soit perceptible. Enfin, la nature complexe des mécanismes physico-chimiques à l’origine des interactions entre le film polymère et la membrane poreuse a été mieux appréhendée durant ce travail. Les conditions nécessaires pour assurer une forte adhésion et les effets conduisant à un mauvais contrôle de l’infiltration ont été partiellement identifiés. Ces résultats ont permis de définir les paramètres clés concernant la préparation de la membrane et la composition de la solution polymère. En associant l’ensemble de ces résultats avec les exigences liées à l’utilisation de l’impression de solutions par jet d’encre, nous avons réalisé, en utilisant cette technique de dépôt, les premiers actionneurs ioniques à base de PEDOT:PSS
Onic electroactive polymer based artificial muscles are promising alternative to traditional actuators, especially where compliant muscle-like response is desirable. Among them, conducting polymer actuators (CPAs) are most promising for biomedical applications, where biocompatibility, compactness and accurate positioning is essential. Nevertheless, development of applicable devices is hold down by their low efficiency and fast performance deterioration. The absence of a tactile, force or position feed-back is another feature limiting the development of functional devices. The goal of this thesis is to develop a fabrication technique for conducting polymer based actuators that could be up-scalable and enable facile integration of sensory feedback. Inkjet printing is key technology in the field of defined polymer deposition as well as in fabrication of strain sensors. It is also one of the most promising alternatives to prevalent fabrication of conducting polymer actuators. Nevertheless, inkjet printed actuators were not yet realized due to rheological properties of conducting polymer solutions that challenge jetting and the complex solution - membrane interactions, that lead to poor adhesion or uncontrolled infiltration. In order to enable this fabrication method, hybrid ion-storing membranes were developed. Argon plasma induced grafting-to of hydrophilic macromonomer with limited-indepth deposition was used to obtain polyvinylidene fluoride (PVDF) membranes with hydrophilic upper surfaces and hydrophobic centre. Functionalized PVDF membranes were shown to withhold good adhesion to the conducting polymer films and preserve electrically insulating layer in between them. Hybrid membranes were demonstrated to be advantageous in fabrication of CPAs by drop casting and enable production of actuators with various morphologies. Furthermore, fabricated poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) based actuators demonstrated long lifetime with no signs of delamination as well as large strain of more than 0.6%. In addition, the complex nature of the physico-chemical mechanisms of the interactions between the polymer film and the porous membrane was better understood during this work. The conditions necessary in order to ensure strong adhesion as well as circumstances leading to uncontrolled infiltration were partially identified. These were used to set up limits to membrane preparation and polymer solution composition. Combining obtained knowledge with known requirements for inkjet printable solutions lead to the realization of the first inkjet printed PEDOT:PSS based ionic actuators

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Duc, Caroline. "Caractérisation et électro-actionnement du PEDOT : PSS en liquide pour son utilisation comme revêtement antisalissure en milieu marin." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10031.

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Les surfaces manufacturées par l’homme sont facilement colonisées par des micro-organismes, qui limitent leurs performances. Ici, nous caractérisons en milieu aqueux, le polymère électro-actif poly(3,4-éthylènedioxythiophène):polystyrène sulfonate, afin d’évaluer son aptitude à limiter l’encrassement biologique en milieu marin. Premièrement, nous nous intéressons à l’évolution de sa mouillabilité et de ses propriétés mécaniques en fonction de sa composition chimique quand il est vieilli ou stimulé électriquement. Nos mesures d’angle de contact sur 6 mois révèlent que, indépendamment du taux de réticulant couramment utilisé pour stabiliser le polymère, son interface change grandement avec le temps et les conditions de caractérisation ou de stockage (influence de l’humidité et de la température). Puis, via des études de microscopie en champ proche, nous quantifions son taux d’hydratation et son élasticité lorsqu’il est immergé. Semblable aux hydrogels, il peut absorber jusqu’à 10 fois son volume et présente un module d’Young inférieur à 1 MPa. Mais le réticulant impacte sévèrement ces propriétés sans assurer une excellente stabilité de l’interface. Enfin, siège de phénomènes d’électromouillage, le polymère subit des variations de 30° de son angle de contact sans présenter d’actionnement mécanique dans nos conditions de test. Deuxièmement, nous étudions l’adhésion de bactéries marines TC8 (Pseudoalteromonas lipolytica) sur le polymère pour évaluer ses propriétés antisalissure en fonction du taux de réticulant. Activable, facilement structurable à l’échelle micrométrique et limitant l’adhésion des bactéries, le PEDOT:PSS est un candidat intéressant pour les revêtements marins
Manmade surfaces often experience rapid fouling by a wide range of micro-organisms which impact their performances. Here, we characterize in aqueous solution, the electro-active polymer poly(3,4-ethylenedioxythiophene):polystyrene sulfonate in order to assess its ability to limit biofouling in marine environment. Firstly, we evaluate the evolution of its wettability and mechanical properties as a function of chemical composition when samples are left to age or are stimulated electrically. Our contact angle measurements performed over 6 months reveal that the polymer interface changes drastically with time and conditions in which the polymer is characterized or stored (influence of the relative humidity and the temperature) regardless of the concentration of cross-linker added to stabilize it and with. Using atomic force microscopy, we quantify the swelling and elastic modulus of the immersed polymer. Like hydrogels, the native polymer is able to absorb 10 times its volume and its Young modulus is smaller than 1MPa. However, the cross-linker addition alters these properties without insuring a good stability of the interface. Applying an electric field as a way to modulate PEDOT:PSS properties is also investigated. We demonstrate a 30° modulation of its contact angle by electrowetting, but no mechanical actuation can be measured under our test conditions. Secondly, we study its anti-biofouling properties as a function of crosslinker concentration. Tests using the marine bacteria TC8 (Pseudoalteromonas lipolytica) show that this polymer limits bacterial adhesion. Electro-active, easily micropatterned and anti-adhesive, PEDOT:PSS could be interesting for marine coatings

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Fenoll, Mathieu. "Optimisation des paramètres d'impression pour l'électronique imprimée sur supports souples." Phd thesis, Grenoble INPG, 2007. http://tel.archives-ouvertes.fr/tel-00176225.

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L'électronique imprimée prend place à l'interface entre les secteurs des industries graphiques et celui de la microélectronique. Les techniques d'impression industrielles classiques que sont l'héliogravure, la flexographie et l'offset présentent le grand avantage d'une productivité élevée en terme de surface imprimée. Une étape de recherche sur la formulation d'encres spécifiques pigmentaires ou à base de polymères fonctionnels se place au cœur de cette problématique. Ce travail de thèse s'inscrit dans le contexte de l'électronique imprimée avec l'optimisation des différents paramètres de transfert intervenant dans l'impression. De même, l'étude de la rhéologie et la physico-chimie des encres est une étape capitale et indissociable de la caractérisation des états de surface des supports. En effet si chaque procédé d'impression possède ses spécificités en termes de propriétés des encres utilisées, une bonne adéquation encre/support est nécessaire afin d'obtenir une impression ayant les caractéristiques recherchées.
Nous avons donc formulé différentes encres polymères conductrices en particulier à base de poly thiophène. Une étude des propriétés de surface et des caractéristiques physiques des différents papiers et plastiques a permis de choisir deux supports tests pour nos impressions. Enfin, une optimisation des paramètres d'impression a démontré l'influence des conditions d'impression sur les caractéristiques des dépôts effectués en particulier en terme de conduction électrique. Un état de l'art et une bibliographie font le point sur les avancées de l'électronique imprimée, ses applications et ses enjeux.

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Troadec, David. "Contribution à l'élaboration et à la caractérisation de diodes électroluminescentes organiques." Limoges, 2001. http://www.theses.fr/2001LIMO0020.

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Ce travail concerne la réalisation et la caractérisation de diodes électroluminescentes organiques (OLEDS) destinées à la fabrication d'écrans plats, souples et consommant peu d'énergie. L'objectif est d'optimiser les performances de diverses structures émettant dans le bleu ou le vert, et d'identifier les phénomènes physiques limitant la conduction, la luminance et le rendement quantique de ces structures. Nous décrivons les étapes technologiques permettant de réaliser les diodes. Les matériaus (organiques et métalliques) sont déposés en film mince (de 10 à 200 nm) à la tournette (polymères) ou par évaporation sous vide (petites molécules et cathode) sur un substrat de verre recouvert d'une couche conductrice et semi-transparentes d'ITO. Pour chacune des structures, des mesures de spectre d'electroluminescence, des caractéristiques d'intensité, de luminance et de rendements en fonction de la tension sont effectuées. Une première étude des structures à base d'Alq3,nous a permis de mettre en évidence les phenomènes limitant les performaces de ces sructures monocouches et de trouver les solutions pour y remédier: élaboration de structures multicouches avec insertion d'une couche d'injection de trous (PEDOT-PSS) ou/et d'une couche de transport de trous (TPD,PVK). Puis nous avons comparé différentes couches émissives, à base de molécules dérivées d'Alq3, afin de déterminer les plus performantes (Bebq2. . . ). Les meilleurs structures émettant dans le bleu fonctionnent quant à elles sur le principe de l'émission de matériaux transporteurs de trous (TPD,TNATA,NPB). Pour confiner et augmenter les recombinaisons radiatives dans la couche émissive nous avons inséré une couche de blocage de trous (BCP) et une couche de transport d'électrons (Alq3,Bebq2). Pour la structure ITO/PEDOT-PSS/Alq3/ Ca/Al,nous avons observé une limitation du courant,suivant le domaine de tension appliquée,soit par des phénomènes d'interface (émission Schottky et effet tunnel) soit par un phénomène de volume (TCL : limitation par les pièges)
Realisation and characterisation of organic light emitting diodes (OLEDS) dedicated to flexible flat panel display with low consumption are studied. The objective is to optimise different structure performances with limit conduction, luminance and quantum efficiency of these structures

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Morais, Rogério Miranda. "Caracterização de dispositivos a base de Pani e Pedot: PSS impressos por impressora jato de tinta visando aplicações como sensores /." Presidente Prudente, 2015. http://hdl.handle.net/11449/154691.

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Orientador: Neri Alves
Banca: Dante Luis Chanaglia
Banca: Felippe Jose Pavinatto
O Programa de Pós Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi
Resumo: Nesta dissertação é apresentada a produção e caracterização de sensores de umidade e amônia totalmente impressos, usando uma impressora jato de tinta comercial. "Tintas" de PANI e PEDOT:PSS foram preparadas e impressas usando uma impressora HP Deskjet D2460. Filmes do polímero condutor PEDOT:PSS foi impresso sobre substratos de papeis e de plásticos e suas propriedades morfológicas e elétricas foram avaliadas em função da densidade superficial de material impresso e da rugosidade dos substratos a fim de obter filmes impressos correntes elétricas suficientes para atuação como eletrodos. Filmes de PANI, com diferentes número de impressões, foram impressos entre os eletrodos de PEDOT:PSS e caracterizações elétricas para o dispositivo PANI/PEDOT/papel antes e após expor ao vapor de HCI, processo no qual promove a dopagem do dispositivo, usando medidas DC e de espectroscopia de impedância (EI). Mostra-se que os resultados, para o sistema impresso PANI/PEDOT/papel, podem ser modelados por um circuito equivalente contendo um resistor R em paralelo com um capacitador C, ambos em série com outro resistor r. As variações de cada parâmetro foram avaliadas em função da exposição a direrentes percentuais de umidade relativa do ar (%UR) e concentrações de amônia (% e ppm). O resistor r, contido no circuito equivalente demonstrou maior resposta e sensibilidade à exposição tanto de umidade quanto de gás amônia mostrando a viabilidade de aplicação deste sistema impresso como sensor. Uma maior sensibilidade para o sistema PANI/PEDOT/papel (sensores de papel) pode ser obtida realizando um tratamento térmico promovendo a evaporação do excesso de HCI no sistema. Para monitoramentos em baixas concentrações de NH3 dispositivos na configuração PANI/PEDOT/PET (sensores plásticos) apresentaram tanto resposta sensitiva quanto tempo de resposta melhores quando comparados aos sensores de papel tratados termicamente
Abstract: This work presents the production and characterization of humidity sensors and fully printed ammonia, using an inkjet printer commercial. "Inks" of PANIN and PEDOT:PSS were prepared and printed using an HP Deskjet D2460 printer. Films of the conducting polymer PEDOT:PSS was printed on paper and plastic substrates and their morphological and electrical properties were evaluated in function of the surface density of printed material and roughness of the substrate in order to obtain printed films with sufficient electrical current to operate as electrodes. Films of PANI, with different number of prints, were printed between the electrodes of PEDOT:PSS AND electrical characterization for the device PANI/PEDOT/paper, before and after exposed to steam HCI, process in which promoting the device doping, were realized using measures DC and impedance spectroscopy (EI). It shows that the results for the printing sytem PANI/PEDOT/paper can be modeled by an equivalent circuit comprising a resistor R in parallel with a capacitor C, both in series with another resistor r. Variations of each parameter were evaluated in function of exposure to different humidity percentage of the air (%RH) and ammonia concentrations (ppm and %). The resistor r contained in the equivalent circuit shown greater response and sensitivity to exposure as much moisture as gas ammonia showing the application feasibility of this system as printed sensor. An increased sensibility to the sytem PANI/PEDOT/paper (paper sensors) can be obtained by performing a heat treatment to promote evaporation of the excess of HCI in the system. For monitoring low concentrations of NH3, devices in PANI configuration PANI/PEDOT/PET (plastic sensors) demonstrated so much an better sensitive response low much an better time response compared to paper sensors treated thermally
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Morais, Rogério Miranda [UNESP]. "Caracterização de dispositivos a base de Pani e Pedot: PSS impressos por impressora jato de tinta visando aplicações como sensores." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/154691.

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Made available in DSpace on 2018-07-27T18:26:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-11-24. Added 1 bitstream(s) on 2018-07-27T18:30:14Z : No. of bitstreams: 1 000864897.pdf: 2555589 bytes, checksum: c920340f90ea5680312e850c433369e4 (MD5)
Nesta dissertação é apresentada a produção e caracterização de sensores de umidade e amônia totalmente impressos, usando uma impressora jato de tinta comercial. Tintas de PANI e PEDOT:PSS foram preparadas e impressas usando uma impressora HP Deskjet D2460. Filmes do polímero condutor PEDOT:PSS foi impresso sobre substratos de papeis e de plásticos e suas propriedades morfológicas e elétricas foram avaliadas em função da densidade superficial de material impresso e da rugosidade dos substratos a fim de obter filmes impressos correntes elétricas suficientes para atuação como eletrodos. Filmes de PANI, com diferentes número de impressões, foram impressos entre os eletrodos de PEDOT:PSS e caracterizações elétricas para o dispositivo PANI/PEDOT/papel antes e após expor ao vapor de HCI, processo no qual promove a dopagem do dispositivo, usando medidas DC e de espectroscopia de impedância (EI). Mostra-se que os resultados, para o sistema impresso PANI/PEDOT/papel, podem ser modelados por um circuito equivalente contendo um resistor R em paralelo com um capacitador C, ambos em série com outro resistor r. As variações de cada parâmetro foram avaliadas em função da exposição a direrentes percentuais de umidade relativa do ar (%UR) e concentrações de amônia (% e ppm). O resistor r, contido no circuito equivalente demonstrou maior resposta e sensibilidade à exposição tanto de umidade quanto de gás amônia mostrando a viabilidade de aplicação deste sistema impresso como sensor. Uma maior sensibilidade para o sistema PANI/PEDOT/papel (sensores de papel) pode ser obtida realizando um tratamento térmico promovendo a evaporação do excesso de HCI no sistema. Para monitoramentos em baixas concentrações de NH3 dispositivos na configuração PANI/PEDOT/PET (sensores plásticos) apresentaram tanto resposta sensitiva quanto tempo de resposta melhores quando comparados aos sensores de papel tratados termicamente
This work presents the production and characterization of humidity sensors and fully printed ammonia, using an inkjet printer commercial. Inks of PANIN and PEDOT:PSS were prepared and printed using an HP Deskjet D2460 printer. Films of the conducting polymer PEDOT:PSS was printed on paper and plastic substrates and their morphological and electrical properties were evaluated in function of the surface density of printed material and roughness of the substrate in order to obtain printed films with sufficient electrical current to operate as electrodes. Films of PANI, with different number of prints, were printed between the electrodes of PEDOT:PSS AND electrical characterization for the device PANI/PEDOT/paper, before and after exposed to steam HCI, process in which promoting the device doping, were realized using measures DC and impedance spectroscopy (EI). It shows that the results for the printing sytem PANI/PEDOT/paper can be modeled by an equivalent circuit comprising a resistor R in parallel with a capacitor C, both in series with another resistor r. Variations of each parameter were evaluated in function of exposure to different humidity percentage of the air (%RH) and ammonia concentrations (ppm and %). The resistor r contained in the equivalent circuit shown greater response and sensitivity to exposure as much moisture as gas ammonia showing the application feasibility of this system as printed sensor. An increased sensibility to the sytem PANI/PEDOT/paper (paper sensors) can be obtained by performing a heat treatment to promote evaporation of the excess of HCI in the system. For monitoring low concentrations of NH3, devices in PANI configuration PANI/PEDOT/PET (plastic sensors) demonstrated so much an better sensitive response low much an better time response compared to paper sensors treated thermally

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Ren, He. "Towards High Performance Pedot: PSS-Free Polymer Solar Cells with Solution-Processed Metal Oxide Thin film as Hole Extraction Layer." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1406378486.

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Augusto, Tatiana. "Síntese química de poli(3,4-etilenodioxitiofeno) (PEDOT): novas arquiteturas para diferentes aplicações." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-02052013-141310/.

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Este trabalho apresenta estudos sobre a síntese química do PEDOT com o objetivo de desenvolver diferentes arquiteturas e propriedades para melhorar a taxa de degradabilidade deste polímero. As estratégias foram as preparações de uma blenda, um copolímero e um nanocompósito. O estudo foi iniciado pela síntese química oxidativa do PEDOT (poli (3,4- etilenodioxitiofeno)) em microestruturas utilizando condições brandas e ambientalmente amigáveis, porém o material obtido não apresentou solubilidade e boas condições de se produzir um filme. Então foi sintetizado quimicamente o PEDOT dopado com PSS (poli estireno sulfonado) (PEDOT:PSS), o mesmo foi usado para preparar blendas com o PLGA (poli (ácido láctico-co-glicólico), para melhorar sua degradabilidade. Foi possível produzir um filme fino e nanoestruturado através de deposição eletrostática camada por camada (LBL) que pode ser utilizado para modificação de eletrodos ou de suportes tridimensionais para engenharia celular. Para garantir a degradabilidade do material, foi realizada a síntese de copolímeros de PEDOT e PLLA (poli(lactídeo)) em que foi variada a proporção de PEDOT na cadeia polimérica. Os copolímeros foram caracterizados por IV, RMN, UV, análises térmicas e submetidos a testes de degradabilidade e de viabilidade celular, apresentando excelentes resultados. Foi possível a obtenção de microfibras deste material. A outra alternativa estudada foi a síntese de um nanocompósito, preparado através da síntese química do PEDOT, partindo do monômero EDOT (3,4- etilenodioxitiofeno)usando HAuCl4 como oxidante e NaPSS como dopante e dispersante. O nanocompósito obtido foi caracterizado apresentando diâmetros médio próximos de 4 nm e com uma estrutura caroço-casca, apresentando nanopartícula de ouro como caroço e o polímero PEDOT:PSS como casca. Foram obtidos filmes deste material por deposição por evaporação de solvente, LBL, utilizando como policátion o PDDA (cloreto de poli (dialil dimetil amônio)) e quitosana, e por deposição eletroforética, que apresentou excelentes propriedades eletrocrômicas como rápidos tempos de respostas com bons contrastes ópticos
This work presents studies about the chemical synthesis of PEDOT (Poly(3,4-ethylenedioxythiophene)) with the aim of preparing different architectures and properties to improvement the degradability rate of this polymer. The strategies used to achieve this pupose were the preparation of polymer blends, copolymers and nanocomposites. The study was started by the chemical synthesis of microstructures PEDOT in mild and environment friendly conditions, but the material did not show solubility which enable film formation. Then, PEDOT was synthetized by chemical synthesis doped with PSS (poly(styrene sulfonic acid)), (PEDOT:PSS) to prepare blends with PLGA (poly(lactic-co-glycolic acid)) to improve its degradability. It was possible to prepare a thin and nanostructured film, by electrostatic layer-by-layer deposition (LBL), which could be used for electrodes or scaffold surface modification. In order to ensure the material\'s degradability, PEDOT and PLLA (poly(lactide)) copolymers were prepared, changing PEDOT proportion in the polymeric structure. The copolymers were characterized by, IR, NMR, UV, thermal analysis and then degradability and cell viability tests, which shown important results. Fibers were able to be obtained with these materials. The next strategy was the preparation of a nanocomposite by one-spot chemical synthesis, initiated by the monomer EDOT (3,4- ethylenedioxythiophene) using HAuCl4 as oxidant and NaPSS as both dopant and dispersant. The nanocomposite obtained was characterized showing diameter of around 4nm and a core-shell structure, with gold nanoparticle as core and PEDOT:PSS as the shell. Films were obtained by this material by casting, by LBL, using PDDA (Poly(diallyldimethylammonium) chloride) and chitosan as polycations, and by electrophoretic deposition. The latter method shows excellent characteristics as fast response time with a good optical contrast

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Ankhili, Amale. "Développement des textiles instrumentés intégrant des électrodes organiques de mesure de bio-potentiel." Thesis, Lille, 2019. http://www.theses.fr/2019LIL1I053.

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Les maladies cardiovasculaires sont les premières causes de mortalités dans le monde. La manière la plus efficace de combattre ces maladies est le suivi en temps réel de l’électrocardiogramme (ECG) qui traduit les signaux électriques générés par les cellules cardiaques. Le signal ECG fournit aux cardiologues toutes les informations nécessaires pour diagnostiquer les pathologies cardiaques. De nos jours, l’électrocardiogramme s’enregistre en cabinet à l’aide d’électrodes cutanées à base d’argent et chlorure de l’argent (Ag/AgCl). Celles-ci ne sont pas conçues pour un usage prolongé et peuvent provoquer des irritations de la peau à cause du gel ionique qui les compose et qui sert à réduire l’impédance de l’interface électrode/peau. Dans cette thèse, des électrodes textiles flexibles fonctionnant sans aucun gel ionique ont été développées en tant qu’alternatives aux électrodes médicales (Ag/AgCl). Notre approche est basée sur la modification d’encres conductrices à base du polymère intrinsèquement conducteur, le poly (3,4-éthylènedioxythiophène) poly(styrènesulfonate) (PEDOT:PSS) compatible avec les substrats textiles choisis. La réalisation des électrodes fait appel à des techniques de fabrication qui peuvent être transférées facilement à l’industrie textile. Des caractérisations ont été mises en places afin d’évaluer la fiabilité de ces systèmes avant et après 50 lavages en machine de laboratoire et domestique. En l’occurrence, la résistivité surfacique des électrodes-capteurs, la modélisation de l’interface électrode/peau, l’analyse du signal ECG en statique et en dynamique, la densité spectrale de puissance du signal ECG, le rapport signal sur bruit (SNR) ont été analysés et comparés à des électrodes commerciales à base d’argent. Comme nos électrodes-capteurs développées possèdent un véritable potentiel clinique et industriel, nous avons également étudié la faisabilité de la connectique et sa durabilité. La solution retenue se compose de deux fils conducteurs en polyamide argenté, existants sur le marché, brodés pour réaliser les connexions entre les électrodes-capteurs textiles et un module électronique flexible à base d’un film composite (polyester-aluminium). De plus deux méthodes d’encapsulation des systèmes ont été également développées en vue de leur protection au lavage et futur commercialisation
Cardiovascular diseases are the leading cause of death worldwide. The most effective way to combat these diseases is the real-time monitoring of the electrocardiogram (ECG) that reflect the electrical signals generated by the heart cells. The ECG signal provides to cardiologists all the information needed to diagnose heart diseases. So far, the electrocardiogram is recorded by using the cutaneous conventional medical electrodes (Ag/AgCl) based on silver and silver chloride. These electrodes are not destined for long-term use and can provoke skin irritation because of the ionic gel that serves to reduce the impedance of the electrode / skin interface. In this thesis, flexible textile electrodes operating without any ionic gel have been developed as alternatives to medical electrodes (Ag/AgCl). Our approach is based on the modification of conductive inks based on the intrinsically conductive polymer, poly (3,4-ethylenedioxythiophene) poly (styrenesulfonate) (PEDOT: PSS) compatible with selected textile substrates. The realization of the electrodes uses manufacturing techniques that can be easily transferred to the textile industry. Characterizations were set up to evaluate the reliability of these systems before and after 50 washes in laboratory and domestic machines. In this case, the surface resistivity of the electrodes-sensors, the modeling of the electrode/skin interface, the analysis of the ECG signal in static and dynamic, the spectral power density of the ECG signal, the signal-to-noise ratio (SNR) were analyzed and compared to commercial silver-based electrodes. As our developed sensor electrodes have a real clinical and industrial potential, we have also studied the feasibility of the connection and its durability. The chosen solution consists of two silver-plated polyamide threads, which are available on the market, embroidered to make the connections between the textile sensor electrodes and a flexible electronic module based on a composite film (polyester-aluminum). In addition, two encapsulation methods have also been developed to protect systems during washing and to make them ready for the market

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Saint-Aubin, Christine de. "Conception de nouveaux matériaux conducteurs extensibles à base de multicouches de polyélectrolytes sur support silicone." Thesis, Mulhouse, 2013. http://www.theses.fr/2013MULH8652/document.

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Cette thèse propose tout d’abord une méthode originale, appelée 2 en 1, de construction contrôlée, couche-par-couche, de films de polyélectrolytes, basée sur le dépôt d’un unique complexe polycation-polyanion. Détaillée dans le cas du poly(éthylènedioxythiophène)-poly(styrènesulfonate) PEDOT-PSS, la méthode est ensuite étendue avec le même succès à d’autres complexes (poly(éthylèneimine) branché-poly(4 styrènesulfonate), poly(diallyldiméthylammonium)-poly(4 styrènesulfonate) et poly(allylamonium)-poly(4 styrènesulfonate)).Les films 2 en 1 de PEDOT PSS sont robustes vis-à-vis d’un recuit thermique et possèdent une conductivité électronique indépendante de leur épaisseur. Cette conductivité peut être améliorée en utilisant un composite contenant des nanoparticules d’or Au Np PEDOT PSS. Des superstructures alternant dépôts de PEDOT PSS et de composite ont, en outre, pu être construites.La construction est contrôlée non seulement sur des substrats rigides (verre, wafer de silicium) mais également sur des substrats élastomère de type silicone (polydiméthylsiloxane PDMS). Le traitement du PDMS par polymérisation plasma d’EDOT sous vide permet le dépôt subséquent de films 2 en 1 de PEDOT PSS. Par ailleurs, la pulvérisation cathodique d’or sur le PDMS permet d’obtenir des conducteurs étirables, de surcroît utilisables comme substrats de films 2 en 1 de PEDOT PSS.Enfin, de nouveaux complexes aqueux synthétisés par voie chimique à partir d’EDOT et d’un polysaccharide (sulfate de chondroïtine A) ont conduit à des films présentant une très bonne conduction qui peut être augmentée par inclusion de nanoparticules d’or. Ces nouveaux composés sont porteurs d’un potentiel très prometteur
This thesis proposes firstly an original method, called 2 in 1 method, for controlled, layer-by-layer, polyelectrolytes film buildup, based on the deposition of a sole polycation-polyanion complex. Detailed on the case of poly(ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS), the method was then extended with the same success to other complexes (branched poly(ethyleneimine)-poly(4 styrenesulfonate), poly(diallyldimethylammonium)-poly(4 styrenesulfonate) and poly(allylamonium)-poly(4 styrenesulfonate)).The 2 in 1 PEDOT PSS films are robust regarding thermal annealing and have an electronic conductivity independent of their thickness. This conductivity can be improved by using a composite containing gold nanoparticles Au Np PEDOT PSS. Superstructures alternating PEDOT PSS and composite depositions were also obtained.Film buildup is controlled not only on rigid substrates (glass, silicon wafer) but also on elastomeric substrates of the silicon type (polydimethylsiloxane PDMS). The treatment of PDMS by vacuum plasma enhanced chemical vapor deposition (PECVD) of EDOT allows subsequent deposition of 2 in 1 PEDOT-PSS films. Besides, gold sputter deposition on PDMS reaches stretchable conductors. Gold sputtered PDMS can further act as a substrate for 2 in 1 PEDOT-PSS films.Finally, new aqueous complexes, chemically synthesized from EDOT and a polysaccharide (chondroitin sulfate A), lead to films which exhibit a very good conduction, which can be improved by the inclusion of gold nanoparticles. These new complexes are very promising in the field of conductive biomaterials

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Pappa, Anna maria. "Metabolite detection using organic electronic devices for point-of-care diagnostics." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEM020/document.

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De nos jours, efficacité et précision des diagnostics médicaux sont des éléments essentiels pour la prévention en termes de santé et permettre une prise en charge rapide des maladies des patients. Les récentes innovations technologiques, particulièrement dans les domaines de la microélectronique et des sciences des matériaux ont permis le développement de nouvelles plateformes personnalisées de diagnostics portatifs. Les matériaux électroniques organiques qui ont déjà par le passé démontré leur potentiel en étant intégrés dans des produits de grande consommation tels que les écrans de smartphones ou encore les cellules solaires montrent un fort potentiel pour une intégration dans des dispositifs biomédicaux. En effet, de par leurs natures et leurs propriétés physiques et chimiques, ils peuvent être à la fois en contact avec les milieux biologiques et constituer l’interface entre les éléments biologiques à l’étude, et les dispositifs électroniques. L’objectif de mes travaux de thèse et d’étudier et évaluer les performances des matériaux organiques électroniques intégrés dans des dispositifs biomédicaux en étudiant leurs interactions avec des milieux biologiques et par l’utilisation et l’optimisation de ces dispositifs permettre la détection de métabolites tel que le glucose ou lactate par exemple. Pendant ma thèse, j’ai notamment créé une plateforme de diagnostics combinant à la fois microfluidique et électronique organique permettant la multi détection de métabolites présents dans des fluides corporels humains, j’ai également conçu des capteurs intégrant des transistors organiques au sein des circuits électroniques classiques afin de détecter la présence des cellules tumorales. D’autres applications biologiques ont également été envisagées telles que la détection d’acides nucléiques par l’utilisation d’une approche simple de biofonctionnalisation. Bien que l’objectif ma thèse était de de créer des capteurs biomédicaux en utilisant une approche in vitro, il pourrait être également possible d’intégrer ces dispositifs « in vivo » ou encore dans des e-textiles
Rapid and early diagnosis of disease plays a major role in preventative healthcare. Undoubtedly, technological evolutions, particularly in microelectronics and materials science, have made the hitherto utopian scenario of portable, point-of-care personalized diagnostics a reality. Organic electronic materials, having already demonstrated a significant technological maturity with the development of high tech products such as displays for smartphones or portable solar cells, have emerged as especially promising candidates for biomedical applications. Their soft and fuzzy nature allows for an almost seamless interface with the biological milieu rendering these materials ideally capable of bridging the gap between electronics and biology. The aim of this thesis is to explore and validate the capabilities of organic electronic materials and devices in real-world biological sensing applications focusing on metabolite sensing, by combining both the right materials and device engineering. We show proof-of-concept studies including microfluidic integrated organic electronic platforms for multiple metabolite detection in bodily fluids, as well as more complex organic transistor circuits for detection in tumor cell cultures. We finally show the versatility of organic electronic materials and devices by demonstrating other sensing strategies such as nucleic acid detection using a simple biofunctionalization approach. Although the focus is on in vitro metabolite monitoring, the findings generated throughout this work can be extended to a variety of other sensing strategies as well as to applications including on body (wearable) or even in vivo sensing

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Torricella, Giulia. "Bioelettronica organica: Nuovi approcci tecnologici per la stimolazione e la rilevazione della comunicazione di cellule neuronali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8520/.

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Il campo della Bioelettronica si è sviluppato a partire dal 18 secolo con l’ esperimento di Luigi Galvani che, applicando uno stimolo elettrico ai muscoli di una rana dissezionata, ne osservò il movimento. Da questo esperimento si è aperta la strada che ha portato ad oggi ad un grande sviluppo tecnologico nella realizzazione di dispositivi elettronici che permettono di offrire un miglioramento generale delle condizioni di vita. Come spesso accade con le tecnologie emergenti, i materiali sono la maggiore limitazione nello sviluppo di nuove applicazioni. Questo è certamente il caso della Bioelettronica. I materiali elettronici organici, nella forma di polimeri conduttivi, hanno mostrato di poter dotare gli strumenti elettronici di grandi vantaggi rispetto a quelli tradizionali a base di silicio, in virtù delle loro proprietà meccaniche ed elettroniche, della loro biocompatibilità e dei bassi costi di produzione. E’ da questi studi che nasce più propriamente il campo della Bioelettronica Organica, che si basa sulla applicazione di semiconduttori a base di carbonio in forma di piccole molecole coniugate e di polimeri, e del loro utilizzo nei dispositivi elettronici. Con il termine di ‘Bioelettronica organica’, quindi, si descrive l’accoppiamento tra dispositivi elettronici organici e il mondo biologico, accoppiamento che si sviluppa in due direzioni: da un lato una reazione o un processo biologico può trasferire un segnale ad un dispositivo elettronico organico, dall’altro un dispositivo elettronico organico può avviare un processo biologico.

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Hempel, Felix [Verfasser], and Markus [Akademischer Betreuer] Hoth. "Organic electrochemical transistors based on PEDOT : PSS for the sensing of cellular signals from confluent cell layers down to single cells / Felix Wolfgang Hempel ; Betreuer: Markus Hoth." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2020. http://d-nb.info/1212433653/34.

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Hempel, Felix Wolfgang [Verfasser], and Markus [Akademischer Betreuer] Hoth. "Organic electrochemical transistors based on PEDOT : PSS for the sensing of cellular signals from confluent cell layers down to single cells / Felix Wolfgang Hempel ; Betreuer: Markus Hoth." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2020. http://d-nb.info/1212433653/34.

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Mastromauro, Michela Pia. "La Bioelettronica Organica: approcci tecnologici per la registrazione, stimolazione e la modulazione di segnali elettrofisiologici di cellule neuronali per finalità terapeutiche nell'ambito della medicina neuro-rigenerativa." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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La Bioelettronica organica è una disciplina sviluppatosi a partire dal XVII secolo con l’esperimento di Luigi Galvani che, applicando uno stimolo elettrico ai muscoli di una rana dissezionata, ne osservò il movimento. La Bioelettronica organica è un’evoluzione della suddetta disciplina nel quale elementi di natura biologica vengono combinati con dispositivi elettronici avanzati, basati sull’utilizzo di materiali organici, con lo scopo di realizzare dispositivi in grado di interagire con la materia vivente per sviluppare nuove metodologie diagnostiche, di analisi e terapeutiche. L’accoppiamento tra dispositivi elettronici organici e il mondo biologico si sviluppa in due direzioni: da un lato una reazione o un processo biologico può trasferire un segnale ad un dispositivo elettronico organico, dall’altro un dispositivo elettronico organico può avviare un processo biologico. In particolare, il mio studio di tesi riguarda l’interazione tra dispositivi elettronici e cellule neuronali in grado sia di riconoscere e analizzare l’attività cerebrale, sia di intervenire sul funzionamento tramite micro-stimoli elettrici localizzati. I materiali elettronici organici, quali polimeri conduttivi e piccole molecole, hanno mostrato di poter consentire la fabbricazione di strumenti elettronici che offrono numerosi vantaggi rispetto a quelli tradizionali a base di silicio, in virtù delle loro proprietà elettroniche e meccaniche, della loro biocompatibilità, dei bassi costi di produzione, così da permettere di minimizzare l’invasività e sviluppare applicazioni sempre più innovative.

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Fuligni, Matteo. "PEDOT:PSS-based conductive Textile for simultaneous detection of sweat analytes." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21204/.

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This thesis is part of the wearable electronic field, and in particular of the Organic BioElecteonic Sensors that have the in-situ real-time monitoring of the health and performance status of the subject as the main goals. With this purpose, textile-based wearable sensors for continuous and simultaneous detection of [Cl–] and pH level have been developed. PEDOT:PSS is the intrinsic conductive polymer used to make the commercial yarns conductive. The coated threads have been functionalized with Ag/AgCl NPs and BTB to make them able to detect [Cl–] and pH level, respectively. The developed sensors end up to be easy-to-make, reproducible with excellent sensitivity and stability both in single and multiple configurations without any interference. The results achieved in this work allow future improvements to develop a new textile-based device that can be easily integrated into clothing, allowing worn it in dealy life.

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Bihar, Eloïse. "Réalisation de dispositifs biomédicaux par impression jet d’encre." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEM036/document.

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De nos jours, le domaine biomédical est en pleine croissance avec le développement de dispositifs thérapeutiques innovants, bas coût, pour le diagnostic, le traitement ou la prévention de maladies chroniques ou cardiovasculaires. Ces dernières années ont connu l’émergence des polymères semi-conducteurs, alternative intéressante aux matériaux inorganiques, présentant des propriétés uniques de conduction ionique et électronique. Tout d’abord, j’ai axé mes travaux de recherche sur le développement et l’optimisation d’une encre conductrice à base de PEDOT:PSS, parfait candidat comme matériau, pour la transduction des signaux biologiques en signaux électriques, compatible avec le process jet d’encre, pour la réalisation de dispositifs imprimés. Puis mes travaux se sont orientés vers la conception et l’étude d’électrodes imprimées sur supports papiers, tatous et textiles permettant des enregistrements long termes d’électrocardiogrammes (ECG) ou électromyogrammes (EMG), présentant des performances similaires aux électrodes commerciales, utilisant un système d’acquisition spécifique pour la mesure d’activités électriques de tissus musculaires. Puis dans un second temps, je me suis penchée sur l’impression sur support papier, de transistors organiques électrochimiques (OECTs) fonctionnalisés, afin de permettre la détection d’éléments biologiques ou chimiques comme l’alcool. Ces travaux proposent une nouvelle voie pour la conception de dispositifs innovants biomédicaux à bas couts, imprimés, permettant la personnalisation des produits pouvant être intégrés dans des dispositifs biomédicaux portables ou dans des vêtements « intelligents »
With the evolution of microelectronics industry and their direct implementation in the biomedical arena, innovative tools and technologies have come to the fore enabling more reliable and cost-effective treatment. In this thesis I focus on the integration of the conducting polymer PEDOT:PSS with printing technologies toward the realization of performant biomedical devices. In the first part, I focus on the optimization of the conducting ink formulation. Following, I emphasize on the fabrication of inkjet printed PEDOT:PSS based biopotential electrodes on a wide variety of substrates (i.e., paper, textiles, tattoo paper) for use in electrophysiological applications such as electrocardiography (ECG) and electromyography (EMG). Printed electrodes on paper and printed wearable electrodes were fabricated and investigated for long-term ECG recordings. Then, conformable printed tattoo electrodes were fabricated to detect the biceps activity during muscle contraction and the conventional wiring was replaced by a simple contact between the tattoo and a similarly ink-jet printed textile electrode.In the last part, I present the potentiality of inkjet printing method for the realization of organic electrochemical transistor (OECTs) as high performing biomedical devices. A disposable breathalyzer comprised of a printed OECT and modified with alcohol dehydrogenase was used for the direct alcohol detection in breath, enabling future integration with wearable devices for real-time health monitoring. Their compatibility with printing technologies allows the realization of low-cost and large area electronic devices, toward next-generation fully integrated smart biomedical devices

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IQBAL, KASHIF. "Study of Rheological Behaviour of Coating Paste containing conductive polymer complex." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20146.

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Conducting polymer coating is the new developing area in the field of advanced textiles. In this project the rheological behaviour of paste containing conducting polymer was studied during formulation to coating application. The literature study is done by keeping all the contents of project in mind and a wide area of conductive polymer, coating methods, binder system and rheology modifier is covered. The rheological behaviour of different fluid containing newtanion and non-newtanion behaviour is discussed for better understanding of the project working. Polyester fabric was coated by knife coating method. In paste formulation, the chemicals used were polyurethane binder with two HEUR based rheology modifiers. A lot of experiments were performed to determine the right amount of rheology modifier alone or in combination for paste formulation and coating application and interesting findings were observed during the experimental work which had been justified in results and analysis. After application, the coated fabric was checked for resistivity.
Program: Magisterutbildning i textilteknologi

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31

Gruia, Violeta-Tincuta [Verfasser], Andreas [Akademischer Betreuer] Bund, Uwe [Gutachter] Ritter, and Geta [Gutachter] Carac. "Preparation and electrochemical performance of PEDOT – AuNPs nanocomposite layers for the selective detection of neurotransmitters / Violeta-Tincuta Gruia ; Gutachter: Uwe Ritter, Geta Carac ; Betreuer: Andreas Bund." Ilmenau : TU Ilmenau, 2016. http://d-nb.info/1178174573/34.

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32

Braendlein, Marcel. "Lithographic fabrication, electrical characterization and proof-of-concept demonstration of sensor circuits comprising organic electrochemical transistors for in vitro and in vivo diagnostics." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEM007/document.

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Grâce à leurs excellentes propriétés mécaniques, électriques et chimiques, les dispositifs organiques électroniques à base de polymères conducteurs peuvent résoudre l’incompatibilité entre les modules électroniques rigides en silicone et les exigences des tissus mous qui constituent l’environnement biologique. Les avancées en matière de semiconducteurs organiques et en microélectronique ont donné naissance à la bioélectronique. Cette discipline emploie des capteurs à des ﬁns diagnostiques, telles que la détection des métabolites ou la mesure d’un potentiel d’action neuronal, et des actionneurs à des ﬁns thérapeutiques, comme l’application locale d’un traitement à l’intérieur même du corps, ou la stimulation cérébrale profonde aﬁn de guérir un trouble neurologique. En bioélectronique, l’utilisation de matériaux organiques, tels que le polymère conducteur poly(3,4-éthylènedioxythiophène) polystyrène sulfonate de sodium (PEDOT:PSS) a permis de développer des composants électroniques biomédicaux de qualité exceptionnelle, comme par exemple le transistor organique électrochimique (OECT), qui ont été testés in vitro et in vivo. Ce manuscrit explique en détail la fabrication, la fonctionnalisation et la caractérisation du OECT à base de PEDOT:PSS. Aﬁn de pouvoir intégrer ce capteur à des systèmes de mesure biomédicaux déjà établis, l’OECT est intégré à des circuits simples, tels qu’un ampliﬁcateur de tension ou un pont de Wheatstone. Ces circuits sont mis à l’épreuve de la pratique clinique, dans le cas de mesures électrocardiographiques, ou de détection de métabolites dans des cellules cancéreuses. Cela permet d’apprécier à la fois leur applicabilité, et leurs limites
Due to their outstanding mechanical, electrical and chemical properties, organic electronic devices based on conducting polymers can bridge the gap between the rigid silicon based read-out electronics and the soft biological environment and will have a huge impact on the medical healthcare sector. The recent advances in the ﬁeld of organic semiconductors and microelectronics gave rise to a new discipline termed bioelectronics. This discipline deals with sensors for diagnostic purposes, ranging from metabolite detection and DNA recognition all the way to single neuronal ﬁring events, and actuators for therapeutic purposes, through for example active local drug delivery inside the body or deep brain stimulation to cure neurological disorder. The use of organic materials such as the conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) in the ﬁeld of bioelectronics has brought about a variety of outstanding electronic biomedical devices, such as the organic electrochemical transistor (OECT), that have been implemented for both in vitro and in vivo applications. The present manuscript gives a detailed explanation of the fabrication, functionalization and characterization of OECTs based on PEDOT:PSS. To be able to intercept this sensor element with traditional biomedical recording systems, the OECT is implemented into simple circuit layouts such as a voltage ampliﬁer or a Wheatstone bridge. These sensor circuits are then applied to real-life biomedical challenges, such as electrocardiographic recordings or metabolite detection in tumor cell cultures, to demonstrate their applicability as well as their limitations

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33

Kim, Youngmin. "Optical studies of the charge localization and delocalization in conducting polymers." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1104360957.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xvi, 145 p.; also includes graphics (some col.) Includes bibliographical references (p. 137-145).

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34

Park, June Hyoung. "Charge transport in organic multi-layer devices under electric and optical fields." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1182273300.

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35

Černošek, Michal. "Impedanční spektroskopie organických vodičů a polovodičů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220994.

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This thesis deals with organic materials and determining their electrical parameters. In the thesis are discussed methods of deposition of organic layers and their measurement. Described are the aspects, which are characteristic for organic materials. They will briefly mention some new components and commercial systems. Special attention is given to conducting polymers and determining their parameters. In the experimental part were measured VA and impedance characteristics of the conductive polymer PEDOT-PSS. The research was also about material degradation in time and effects of thickness on the electrical parameters.

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36

Theibert, Dustin. "Organic Photovoltaic Optimization: A Functionalized Device Based Approach." Bowling Green State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1383508741.

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37

Song, Cheng-Wei, and 宋政緯. "The Effect of Al Doping on the Optoelectronic Properties of ZnO/PEDOT/PSS Nanocomposite Film." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/r73ff9.

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碩士
國立臺北科技大學
資源工程研究所
102
In this study, transparent and conductivity nanocomposite films of Al doped ZnO nanoparticles and PEDOT/PSS in PEG300 were coated on glass substrate by using the spin coating method. The experiment was divided into two parts. First, Un-doped ZnO and Al (0.3–4.0 at.%) doped ZnO nanopowders (AZO) were prepared by the Pechini method, heat treatment at 500oC for 3 h in air, and then analyzed by SEM-EDX、TEM、XRD、Raman spectra、UV-Vis、XPS and Four point probe. The morphology and grain size were found to be controlled by heat treatment temperature and the concentrations of chelating aging, citric acid and crosslinking agents, PEG2000. XRD patterns of AZO powders were similar to those of ZnO powders, indicating that Al ions were substituted with Zn atoms in the ZnO structure. From the XRD data, the grain size of the A(1.7 at.%)ZO nanoparticles revealed a minimum at 23 nm with optical band gap at 3.14 eV. With increasing Al dopant, the AZO nanoparticle increase their defect concentration (oxygen vacancies) resultant from Raman spectra. The electrical sheet resistance of the A(1.7 at.%)ZO reached a minimum of 5.36 x 105 Ω/sq. Second, modification of the electrical properties of PEDOT/PSS by the incorporation into it of ZnO nanoparticles which were synthesized by solution mix containing PEG300. In the nanocomposite, there is a change of chemical structure from a mixture of benzoid and quinoid to a mostly quinoid was observed. This structural changes result in an enhancement of the 2 orders of magnitude in electrical conductivity. The best A(1.7 at.%)ZO/PEDOT/PSS/PEG300 films from Hall work showed the greatest conductivity at 6.47 x10-1 S/cm with the hightest transmittance at 75%. Moreover, the films prepared from two types of commercial product and that from Pechini method ie nano composite of ZnO and PEDOT/PSS/PEG films was investigated by FTIR and Raman for comparison.

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Lin, Yu-Cheng, and 林俞成. "Pattern Formation of PEDOT : PSS as Electrodes by Reversal Imprinting." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/61735601150425883513.

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碩士
國立成功大學
材料科學及工程學系碩博士班
96
Organic devices with advantages of flexibility could make with pattern of organic polymer quickly by imprinting. It has low cost and potential of output for developing organic devices. The conducting polymer (PEDOT : PSS) is water soluble slightly, so it is difficult to make micropatterns by photolithography process. We use reversal imprinting – microtransfer molding to prepare conducting polymeric patterns without residual layer with aspect ratio about 1:1 under appropriate conditions of polymeric concentration, imprinting temperature, and pressure to avoid scaling pattern. This thesis also shows a kind of novel reversal imprinting – solvent assisted reversal imprinting. We only control the content of solvent (water) precisely to be able to transfer conducting polymeric patterns onto substrate quickly and effectively. The resolution of conducting polymeric patterns can achieve the size of 2.5μm. The conductivity of bare PEDOT : PSS is enhanced from 0.25 to 236±10 S/cm through organic solvent addition. The conductivity of solvent – PEDOT : PSS is further enhanced from 236±10 to 376±15 S/cm as added with Au nanorods. The transferred conducting polymeric patterns have been demonstrated for applications : (1) drop deposition of ZnO nanorods between the transferred conducting polymeric patterns to fabricate Schottky diode, (2) combine pentacene-based TFT with SiO2 as gate dielectric layer to have Ion/Ioff of 100 and mobility of 0.007cm2/V-s. Besides, we use PEDOT : PSS / ZnO nanorods composite film to fabricate UV light sensor.

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Kuo, Kai-Shiang, and 郭凱翔. "Preparation and Properties of PSS-PBA/PEDOT Flexible Conductive Films." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/44094346943132946842.

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碩士
國立臺灣大學
化學工程學研究所
99
The aim of this study was to synthesize the Poly(styrenesulfonate)-Poly(butyl acrylate)/Poly(3,4-ethylenedioxythiophene) (PSS-PBA/PEDOT) core-shell complex conductive dispersion. In this study, the flexible conductive film was fabricated by spin coating the PSS-PBA/PEDOT complex dispersion on PET and glass substrate. The optoelectronic properties of the flexible conductive film such as transparency, conductivity, and flexibility were investigated to compare the relationship between the monomer content and polymeric surfactant. This study included two parts. In first part, by using Poly(4-styrenesulfonic acid) (PSSH) and Poly(Sodium styrenesulfonate) (PSSNa) as the surfactant, PSSH-PBA and PSSNa-PBA core-shell latex were synthesized from Butyl Acrylate (BA) monomer via emulsion polymerization. Then, the effect of the two kinds of polymeric surfactants with BA monomer in different ratio was discussed. Furthermore, the glass transition temperature (Tg), particle size and morphology were characterized by Differential Scanning Calorimeter (DSC), Dynamic Light Scattering Analyzer (DLS) and Transmission Electron Microscope (TEM), respectively. It was found that the Tg of both PSSH-PBA and PSSNa-PBA are approximate to the Tg of pure PBA. In addition, the particle size of PSSNa-PBA latex increased slightly with the proportion of BA increased; on the other hand, the particle size of PSSH-PBA latex increased with the proportion of PSSH increased. In second part, the flexible core-shell complex conductive dispersion, PSSNa-PBA/PEDOT and PSSH-PBA/PEDOT, were carried out via oxidative polymerization of EDOT monomer. In which the shell of PSS-PBA core-shell latex was served as the template in water. Dynamic Light Scattering Analyzer (DLS) and Transmission Electron Microscope (TEM) were employed to detect the particle size and morphology, respectively. By spin coating the complex conductive dispersion to form the PSS-PBA/PEDOT thin film, the conductivity, transparency and flexibility could be measured. It showed that the PSS-PBA/PEDOT complex thin film owned superior transparency (transmittance > 80% at 100 nm film thickness). The conductivity of the PSSH-PBA/PEDOT thin film synthesized was obviously better than the PSSNa-PBA/PEDOT film. Furthermore, the flexibility of the PBA-PSS/PEDOT thin film effectively increased due to the introduction of PSS-PBA core-shell latex.

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Chen, Yu-Hao, and 陳育豪. "Investigation of multiple processing for improvement of PEDOT: PSS films." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/5h36z4.

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碩士
國立虎尾科技大學
電子工程系碩士班
102
In this study, the multiple processing for improvement of PEDOT: PSS films were investigated. The PEDOT: PSS solution was improved by doping organic solvent. The sheet resistance of PEDOT: PSS film was decreased from 140 to 58.7 ohm/square with the increasing time of heating-stirred. It was reduced nearly 58%. The improvement of doping effect was attributed to induce the reorientation of PEDOT grains and PSS chains in PEDOT: PSS solution. And PEDOT grains and PSS chains were aggregated gradually in the heating-stirred process. The PEDOT: PSS film was used as the anode of solar cell to replace ITO film. The basic device structure was fabricated as follows: PEDOT: PSS/ CuPc/ C60/ BCP/ Ag. The PCE of organic solar cell was used for verification of the formula of merit values. The best value of the φTC is 3.04×10-3 ohm-1 square. And the best PCE of organic solar is 0.203%. The PCE of organic solar is consistent with the merit value. This indicates that the merit value can be represented for the PCE of organic solar cell. Based on the optimal conductivity of PEDOTPSS film, we improved surface of PEDOT: PSS film by using the acid solution. After treatment of acid solution, the sheet resistance of PEDOTPSS film can be further decreased from 58.7 to 43 ohm/square. In addition, the transmittance of PEDOTPSS film was slightly increased from 77.2% to 82.6% in the visible wavelength range from 400 to 700 nm. The conductivity is further enhanced because the surface of PEDOT: PSS films were relatively more PEDOT conductive grains after treatment of acid solution.

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HSIEH, YU-LUN, and 謝雨倫. "Flexible electrothermal film heaters based on nanocarbon /PEDOT : PSS composites." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/67d975.

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碩士
國立中正大學
化學工程研究所
107
Electrothermal film heater has been widely used in the broad area including vehicle defrosting windows, thermal therapy device, heating element. Among them, flexible or stretchable electrothermal film heater has attracted great attention. Conducting polymer (e.g. PEDOT : PSS) is one of the most commonly used conducting material for flexible electrothermal film heater. In this study, to enhance the conductivity of conducting polymer and improve the performance of electrothermal film heater, four different kinds of nanocarbon materials, including commercial carbon black (model: Super P), coke supplied by CPC Corporation, Taiwan (model: CPCA), carbon nanocapsules (model: CNC, provided by Nano lab, CHE, NCCU), and carbon nanofiber (CNT, Lab-made) are introduced to mix with conducting polymer, poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS, model: PH1000) to form the composite as the conductive ink. On the other hand, stretchable thermoplastic polyurethane (TPU, model: 1185A) elastic nanofiber mat is fabricated by electrospinning method, which is used as the substrate. Then, the flexible electrothermal film heater is prepared by spray coating of the conductive ink on the TPU nanofiber mat. The electrothermal performances correlated with four different carbon materials are investigated in terms of applied voltage, response time, conductivity, and their basic carbon properties. The results show the CNC/PEDOT : PSS (40 mg/1.5 ml) coated TPU film has higher conductivity and better electrothermal property compared to the PEDOT : PSS and other carbon materials/PEDOT:PSS coated films. The average temperature of 88.7 °C can be reached at voltage of 10 V and maintained at around 50 °C under 30% stretch deformation. Moreover, the flexible electrothermal film heater can remain its good heating performances under repeatedly bending test for 5 times and long-term test for 1 hour. Finally, the flexible electrothermal film heater has been demonstrated to has good electrothermal property in two applications: wearable thin-film heaters and water heater. These results provide clear evidence for its potential and widespread applications in the future.

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SHYR, UIN-TING, and 石昀庭. "The Solvent Effect on the Conductivity and Morphology of PEDOT: PSS Blend." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8jxdyw.

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碩士
國立臺北科技大學
分子科學與工程系有機高分子碩士班
107
The thesis is composed of several parts: the first is the main process of synthesis PEDOT: PSS； the second is to compare the properties with the same polyelectrolyte we purchased from AGFA ( ORGACON ICP 1050 )；and the final part we used FTIR, XRD, SEM and 4 - Point Probe to analyze the effect between solvents and the PEDOT: PSS blend. From the experimental Results of Pei - Hsuan Tseng, we adjusted the weight ratio from PSS solution to solvent to 0.4 wt% - 6.5 wt%. We also learned the process of synthesis PSS and EDOT would got a better polymerization in room temperature water bath ( 20。C ) and nitrogen system, and it truly enhanced the conductivity fom initial 0.2 S/cm to almost 0.6 S/cm The second part we compared the properties of the conductivity and morphology between products and AGFA standard, after the different surface treatment process and we foundd out if the process used the stroung polarity solvents to mix as the coating solution, it will make conductivity more stroung. We also mixed liquid ion ( EMIM: TCM ) in to the solution and prepared another type of flims, it also enhanced the PEDOT: PSS conductivity. At the final part we tried to use XRD to analyzed the different of morphology between AGFA standard and our products. We even used SEM to scan the surface of films, and the results proved that we had synthesized a similar structure of PEDOT: PSS asAGFA standard.

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Liu, Yu-Ling, and 劉鈺玲. "Preparation and Application of g-C3N4 / PEDOT: PSS Conductive Polymer Composite Fiber." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/wvm94t.

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碩士
中原大學
化學工程研究所
106
With the advancement of science and technology, industrial pollution and energy crisis have become more and more severe, and environmental issues have gradually received attention. Photocatalysts with advantages of tunable optical and electrical properties, low cost, high photocatalytic activity, chemical stability and non-toxicity are widely studied by scientists. In this study, composite fiber materials composed of g-C3N4 and PEO/PEDOT:PSS were prepared for photocatalytic reaction. g-C3N4 was prepared by high temperature calcination using urea as a precursor, followed by functionalization of ethanolamine (MEA) solution to obtain amine-functionalized g-C3N4, and PEO/PEDOT:PSS fibers were prepared by electrospinning technology. The composite fiber is further subjected to a photocatalytic reaction. The experimental results show that the amine-functionalized g-C3N4 solely attaches to the surface of g-C3N4 without affecting the original morphology and damaging the initial g-C3N4 structure. Moreover the optimal spinning conditions for electrospinning PEO/PEDOT:PSS fibers can be obtained by controlling the ambient humidity, operating voltage, flow rate, and viscosity of PEO. In addition, we improved the moisture instability of PEO/PEDOT:PSS nanofibers by utilizing the crosslinking reaction of PSS and PEO at high temperature. Finally, in the photocatalytic test, we found that the heating time of the MEA would affect the adsorption of g-C3N4, which would affect the performance of composite fibers in photocatalytic test.

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44

Zhanshayeva, Lyazzat. "Towards macroscopic modeling of electro-thermo-mechanical couplings in PEDOT/PSS: Modeling of moisture absorption kinetics." Thesis, 2018. http://hdl.handle.net/10754/628057.

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Organic conducting polymer, poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS), is widely recognized for its electro-actuation mechanism and is used in flexible electronics. Its high potential as actuator is based on a strong coupling between chemical, mechanical and electrical properties which directly depends on external stimuli. There is no model today to describe the interplay between moisture absorption, mechanical expansion and electrical stimulus. Elucidating the role of each component in the effective actuation properties is needed to further optimize and tailor such materials. The objective of this thesis is to develop a macroscopic model to describe water sorption kinetics of the PEDOT:PSS film. We used gravimetric analysis of pure PEDOT:PSS film of three different thicknesses to investigate absorption kinetics over a broad range of temperatures and relative humidity. Our results revealed that the moisture uptake of PEDOT:PSS film does not follow Fickian diffusion law due to the retained amount of water after desorption process. We used an existing diffusionreaction model to describe this behavior, and COMSOL Multiphysics and MATLAB software programs to implement it. We observed that the generic model we used in our work could predict polymer behavior with 95% accuracy. However, our model was not able to properly represent the data at very high relative humidity at low temperature, which was attributed to the excessive swelling of the film. Also, we examined a relation between the moisture content of PEDOT:PSS and its mechanical strain and electrical conductivity. The results presented here are the first step towards a general multiphysics electro-thermo-mechanical description of PEDOT:PSS based actuators.

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45

Wang, Ting-Yi, and 王婷儀. "Electro-polymerization functionalized graphene / PEDOT-PSS composite film used in dye-sensitized solar cells." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3sq66q.

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碩士
國立臺北科技大學
化學工程研究所
105
Because of high conductivity and excellent environmental stability, PEDOT-PSS is considered to a successful conductive polymer. But compared to platinum, which is more commonly used as a counter electrode of dye-sensitized solar cell, PEDOT-PSS has less oxidation-reduction ability and resulting in poor efficiency, although it can significantly reduce costs. 　　Therefore, we use graphene, which has good oxidation-reduction ability and excellent electrical conductivity. We functionalized graphene, and used electrochemical polymerization to form a functionalized graphene / PEDOT-PSS composite film, hoping to obtain a counter electrode which has excellent oxidation-reduction ability, and getting a higher value of light-to-electron conversion efficiency. 　　The functionalized graphene is identified by the Fourier transform infrared spectrometer. Scanning electron microscope and cyclic voltammetry were used to observe the surface distribution and redox potential of functionalized graphene / PEDOT-PSS composite film. Different proportions of functionalized graphene / PEDOT-PSS electrode were packaged into the dye-sensitized solar cell, and using simulated sunlight system, AC impedance test to obtain photoelectric conversion efficiency and resistance. In this experiment, the PEDOT-PSS counter electrode which added 0.01 wt% of carboxylate functionalized graphene has best efficiency of dye-sensitized solar cell, and the light-to-electron conversion efficiency was being risen from 2.58% to 3.36%. And “over-oxidation” reaction should be avoided when the electrochemical polymerization is operating, or the conductivity of PEDOT-PSS will intensely decrease.

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Li, Dong-Lin, and 李東霖. "Preparation of Functionalized Graphene / PEDOT-PSS Composite Film and Application to Dye-sensitized Solar Cells." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/xgy2mc.

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碩士
國立臺北科技大學
化學工程研究所
101
In this study we improve the DSSC of battery. There are many dye-sensitized solar cells using platinum as counter electrode. But the platinum is too expensive that we hope to use the low cost conducting polymer as counter electrode materials. Because the PEDOT-PSS of conductive polymer that oxidation reduction is bad, we add grapheme which not only has a good oxidation-reduction ability but also the conductivity is high. We use the simple process to manufacture the dye-sensitized solar cells which are able to use in large-scale industrial manufacturing. Matrix includes ITO glass as well as flexible element(ITO-PET). we use X-ray Diffraction, Scanning Electron Microscopy, Energy Dispersive Spectrometer, UV–visible to identify the property of optical, chemistry, film surface as we manufacture dye-sensitized solar cell.Batteries with different ratios of the graphene on the electrode package use the system of simulated sunlight, EIS, to get photoelectric conversion efficiency and the resistor of the cell. The ITO glass which is added 0.1g ofgrapheme has the best efficiency , and the photoelectric conversion efficiency is 3.78%. Regarding the flexible element, the one with 0.5g of grapheme has the best efficiency, the photoelectric conversion efficiency is 0.3552%. Efficiency in flexible element above to be strengthened.

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47

Tsai, Tsung-che, and 蔡宗哲. "Effect of Doping Polyalcohol and Carbon Nanotube on Transparency and Electric Characteristics of PEDOT-PSS Film." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/58439527292900117666.

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48

Chiu, Chun-Wen, and 邱俊文. "Enhanced conductivity of PEDOT: PSS electrode by different treatment for ITO-free organic light emitting diodes." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/c326y5.

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碩士
國立中山大學
光電工程學系研究所
102
Flexibility is one of the biggest features of OLED. However, there is a big problem brought by the ITO anode. ITO will crack when the substrate is bent in a large angle and this might result in decreasing the conductivity. Different treatments are used to enhance the conductivity of PEDOT:PSS thin film which can be an anode in organic light emitting diodes. In this research, the thin films of PEDOT:PSS with different treatments of H2SO4 and Glycerol were fabricated to replace the ITO layer as an anode to develop the flexible OLEDs. All different treated films were investigated and compared with each other in the difference of optical transmittance, work function, conductivity, surface roughness, surface morphology, and stability. It was found that after treatment the conductivity of PEDOT: PSS films can be effectively improved from 0.3 (S/cm) to 528 (S/cm) with H2SO4 treatment and from 0.3 (S/cm) to 588 (S/cm) with Glycerol treatment. Then The devices were fabricated by using the treated PEDOT:PSS thin film for an anode. The device structure is PEDOT:PSS(PH1000)(170 nm)/ /NPB(50 nm)/Alq3(60 nm)/LiF(0.8 nm)/Al(200 nm),and the device area is 0.03 cm2.The result shows that Glycerol treated PEDOT:PSS anode has the better performance. It exhibits maximum luminance 387.7 cd/m2 .The maximum current and power efficiency are 1.29 cd/A and 0.81 lm/W. We expect it will replace ITO to develop flexible OLED.

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Pathak, Chandra Shakher. "Investigation of pedot : pss/si heterojunctions and grsphene/si schottky diodes for potential application in photovoltai." Thesis, 2018. http://localhost:8080/iit/handle/2074/7555.

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50

Sangeeth, Suchand C. S. "Charge Transport In Conducting Polymers, Polymer-Carbon Nanotube Composites And Devices." Thesis, 2012. http://etd.iisc.ac.in/handle/2005/2279.

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The Thesis reports charge transport studies on conducting polymers, polymer carbon nanotube composites and organic semiconductor devices. Conducting and semiconducting polymers consisting of π-conjugated chains have attracted considerable attention as they combine the optoelectronic properties of semiconductors with mechanical properties and processing advantages of plastics. The chemical/electrochemical/photodoping of these semiconducting polymers can tune the Fermi levels and conductivity in a controlled way, and hence the properties of devices can be easily tailored to suit in several applications. Carbon nanotube (CNT) is another another novel promising material for electronic/optoelectronic applications. Lately there has been a great interest in developing composites of polymer and CNTs to utilize the advantages of both CNTs and polymers. The inclusion of CNTs in polymers improves the mechanical, electrical and thermal properties since the aspect ratio (ratio of length to diameter) is very large, as well its density is rather low. The Thesis consists of 6 chapters. First chapter is a brief introduction of general and transport properties of conducting polymers and polymer-carbon nanotube composites. In Chapter 2, the sample preparation and experimental techniques used in this work are discussed. The charge transport in poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) is presented in Chapter 3. Chapter 4 focuses on the transport measurements in the polymer-CNT composite samples. Chapter 5 elaborates the ac and dc characterization of organic field-effect transistors (OFETs). And chapter 6 presents the conclusion and future directions of the work that has been presented in the Thesis. Chapter 1: In the scientific and technological revolution of the last few years, the study of high performance materials has been steadily increasing including the study of carbon-based materials. Conducting polymers have special properties that are interesting for this new technology. The charge transport in conjugated polymers is important to optimize the performance of devices. The discovery of CNTs with exceptional thermal, mechanical, optical, electrical and structural properties has facilitated the synthesis of new type of nanocomposites with very interesting properties. Nanocomposites represent a guest-host matrix consisting of easily processible functionalized conjugated polymer as host, incorporating CNTs as fillers with versatile electronic and magnetic properties, which provide a wide range of technological applications. To optimize their electrical properties it is essential to understand the charge transport mechanism in detail. Chapter 2: The multi-wall carbon nanotubes (MWNTs) grown by thermal chemical vapor deposition (CVD) are mixed with a 1:1 mixture of 98% H2SO4 and 70% HNO3 to produce sulfonic acid functionalized multi-wall carbon nanotubes (s-MWNTs). The s-MWNTs are dispersed in a solution of Nafion by ultrasonication and then cast on a glass substrate and slowly dried by moderate heating to obtain the composite films. Polyaniline (PANI)-MWNT composites were obtained by carrying out the chemical synthesis of nanofibrilar PANI in the presence of CNTs. This water dispersible PANIMWNT composite contains well segregated MWNTs partially coated by nanofibrilar PANI. The ac and dc charge transport measurements suggest hopping transport in these materials. OFETs are fabricated with pentacene, poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene)(PBTTT) and poly(3-hexylthiophene) (P3HT) as active materials. A novel technique is used to characterize the acphotoresponse of these OFETs. Chapter 3: Charge transport studies on PEDOT-PSS have been carried out and found that it correlates with the morphology. The dc conductivity of PEDOT–PSS shows enhanced delocalization of the carriers upon the addition of dimethyl sulfoxide (DMSO) and this is attributed to the extended chain conformation. PEDOT-PSS is known to form a phase-segregated material comprising highly conducting PEDOT grains that are surrounded by a sea of weakly ionic-conducting PSS and a wide variation in the charge transport properties of PEDOT-PSS films is attributed to the degree of phasesegregation of the excess insulating polyanion. The magnetotransport and temperature dependent ac transport parameters across different conducting grades of PEDOT-PSS processed with DMSO were compared. Depending on the subtle alterations in morphology, the transport at low temperatures is shown to vary from the hopping regime (Baytron P) to critical regime of the metal-insulator transition (Baytron PH510) There is a significant positive magnetoresistance (MR) for P–films, but this is considerably less in case of PH510-film. From the low temperature ac conductance it is found that the onset frequency for PH510 is nearly temperature independent, whereas in P type it is strongly temperature dependent, again showing the superior transport in PH510. The presence of ‘shorter network connections’ together with a very weak temperature dependence down to ~ 5 K, suggest that the limitation on transport in PH510 arises from the connectivity within the PEDOT-rich grain rather than transport via the PSS barriers. Chapter 4: DC and AC charge transport properties of Nafion s-MWNT and PANI-MWNT composites are studied. Such a detailed investigation is required to optimize the correlation among morphology and transport properties in these composites towards applications in field-effect transistors, antistatic coating, electromagnetic shielding, etc. The conductivity in Nafion s-MWNT shows a percolative transport with percolation threshold pc = 0.42 whereas such a sharp percolation is absent in PANI-MWNT composite since the conduction via PANI matrix smears out the onset of rapid increase in conductivity. Three-dimensional variable range hopping (VRH) transport is observed in Nafion s-MWNT composites. The positive and negative MR data on 10 wt. % sample are analyzed by taking into account forward interference mechanism (negative MR) and wave-function shrinkage (positive MR), and the carrier scattering is observed to be in the weak limit. The electric-field dependence, measured to high fields, follows the predictions of hopping transport in high electric-field regime. The ac conductivity in 1 wt. % sample follows a power law: ( )  A s , and s decreases with increasing temperature as expected in the correlated barrier hopping (CBH) model. In general, Mott’s VRH transport is observed in PANI-MWNT samples. It is found that the MWNTs are sparingly adhered with PANI coatings, and this facilitates inter-tube hopping at low temperatures. The negative MR of MWNT-PANI composites suggest that the electronic transport at low temperatures is dominated by MWNT network. AC impedance measurements at low temperatures with different MWNT loading show that ac conductivity become temperature independent as the MWNT content increases. The onset frequency for the increase in conductivity is observed to be strongly dependent on the MWNT weight percentage, and the ac conductivity can be scaled onto a master curve given by  ( )  0[1 k( 0 )s ]. Chapter 5: Organic field-effect transistors (OFETs) based on small molecules and polymers have attracted considerable attention due to their unique advantages, such as low cost of fabrication, ease of processing and mechanical flexibility. Impedance characterization of these devices can identify the circuit elements present in addition to the source-drain (SD) channel, and the bottlenecks in charge transport can be identified. The charge carrier trapping at various interfaces and in the semiconductor can be estimated from the dc and ac impedance measurements under illumination. The equivalent circuit parameters for a pentacene OFET are determined from low frequency impedance measurements in the dark as well as under light illumination. The charge accumulation at organic semiconductor–metal interface and dielectric semiconductor interface is monitored from the response to light as an additional parameter to find out the contributions arising from photovoltaic and photoconductive effects. The shift in threshold voltage is due to the accumulation of photogenerated carriers under SD electrodes and at dielectric–semiconductor interface, and also this dominates the carrier transport. Similar charge trapping is observed in an OFET with PBTTT as the active material. This novel method can be used to differentiate the photophysical phenomena occurring in the bulk from that at the metal-semiconductor interface for the polymer. Chapter 6: The conclusions from the various works presented in the thesis are coherently summarized in this chapter. Thoughts for future directions are also summed up.

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