Showing papers on "Conductive polymer published in 2007"
01 Jan 2007
TL;DR: Theoretical models and simulations of polymers have been used to study the molecular dynamics of different molecular architectures and properties of polymeric networks and gels as discussed by the authors, including the properties of different types of networks.
Abstract: Preface to the Second Edition. -Preface to the First Edition. -STRUCTURE. -Chain Structures. -Names, Acronyms, Classes, and Structures of Some Important Polymers. -THEORY. -The Rotational Isomeric State Model. -Computational Parameters. -Theoretical Models and Simulations of Polymer Chains. -Scaling, Exponents, and Fractal Dimensions. -THERMODYNAMIC PROPERTIES. -Densities, Coefficients of Thermal Expansion, and Compressibilities of Amorphous Polymers. -Thermodynamic Properties of Proteins. -Heat Capacities of Polymers. -Thermal Conductivity. -Thermodynamic Quantities Governing Melting. -The Glass Temperature. -Sub-Tg Transitions. -Polymer-Solvent Interaction Parameter c. -Theta Temperatures. -Solubility Parameters. -Mark-Houwink-Staudinger-Sakurada Constants. -Polymers and Supercritical Fluids. -Thermodynamics of Polymer Blends. -SPECTROSCOPY. -NMR Spectroscopy of Polymers. -Broadband Dielectric Spectroscopy to Study the Molecular Dynamics of Polymers Having Different Molecular Architectures. -Group Frequency Assignments for Major Infrared Bands Observed in Common Synthetic Polymers. -Small Angle Neutron and X-Ray Scattering. -MECHANICAL PROPERTIES. -Mechanical Properties. -Chain Dimensions and Entanglement Spacings. -Temperature Dependences of the Viscoelastic Response of Polymer Systems. -Adhesives. -Some Mechanical Properties of Typical Polymer-Based Composites. -Polymer Networks and Gels. -Force Spectroscopy of Polymers: Beyond Single Chain Mechanics. -REINFORCING PHASES. -Carbon Black. -Properties of Polymers Reinforced with Silica. -Physical Properties of Polymer/Clay Nanocomposites. -Polyhedral Oligomeric Silsesquioxane (POSS). -Carbon Nanotube Polymer Composites: Recent Developments in Mechanical Properties. -Reinforcement Theories. -CRYSTALLINITY AND MORPHOLOGY. -Densities of Amorphous and Crystalline Polymers. -Unit Cell Information on Some Important Polymers. -Crystallization Kinetics of Polymers. -Block Copolymer Melts. -Polymer Liquid Crystals and Their Blends. -The Emergence of a New Macromolecular Architecture: 'The Dendritic State'. -Polyrotaxanes. -Foldamers: Nanoscale Shape Control at the Interface Between Small Molecules and High Polymers. -Recent Advances in Supramolecular Polymers. -ELECTRO-OPTICAL AND MAGNETIC PROPERTIES. -Conducting Polymers: Electrical Conductivity. -Conjugated Polymer Electroluminescence. -Magnetic, Piezoelectric, Pyroelectric, and Ferroelectric Properties of Synthetic and Biological Polymers. -Nonlinear Optical Properties of Polymers. -Refractive Index, Stress-Optical Coefficient, and Optical Configuration Parameter of Polymers. -RESPONSES TO RADIATION, HEAT, AND CHEMICAL AGENTS. -Ultraviolet Radiation and Polymers. -The Effects of Electron Beam and g-Irradiation on Polymeric Materials. -Flammability. -Thermal-Oxidative Stability and Degradation of Polymers. -Synthetic Biodegradable Polymers for Medical Applications. -Biodegradability of Polymers. -Properties of Photoresist Polymers. -Pyrolyzability of Preceramic Polymers. -OTHER PROPERTIES. -Surface and Interfacial Properties. -Acoustic Properties. -Permeability of Polymers to Gases and Vapors. -MISCELLANEOUS. -Definitions. -Units and Conversion Factors. -Subject Index
2,230 citations
TL;DR: It appears that nanotubes are a perfect conducting additive and/or support for materials with pseudocapacitance properties, e.g. MnO(2), conducting polymers.
Abstract: The most commonly used electrode materials for electrochemical capacitors are activated carbons, because they are commercially available and cheap, and they can be produced with large specific surface area. However, only the electrochemically available surface area is useful for charging the electrical double layer (EDL). The EDL formation is especially efficient in carbon pores of size below 1 nm because of the lack of space charge and a good attraction of ions along the pore walls. The pore size should ideally match the size of the ions. However, for good dynamic charge propagation, some small mesopores are useful. An asymmetric configuration, where the positive and negative electrodes are constructed from different materials, e.g., activated carbon, transition metal oxide or conducting polymer, is of great interest because of an important extension of the operating voltage. In such a case, the energy as well as power is greatly increased. It appears that nanotubes are a perfect conducting additive and/or support for materials with pseudocapacitance properties, e.g. MnO2, conducting polymers. Substitutional heteroatoms in the carbon network (nitrogen, oxygen) are a promising way to enhance the capacitance. Carbons obtained by one-step pyrolysis of organic precursors rich in heteroatoms (nitrogen and/or oxygen) are very interesting, because they are denser than activated carbons. The application of a novel type of electrolyte with a broad voltage window (ionic liquids) is considered, but the stability of this new generation of electrolyte during long term cycling of capacitors is not yet confirmed.
1,762 citations
TL;DR: In this article, a review of gas sensors fabricated by using conducting polymers such as polyaniline (PAni), polypyrrole (PPy) and poly (3,4-ethylenedioxythiophene) (PEDOT) as the active layers has been reviewed.
Abstract: The gas sensors fabricated by using conducting polymers such as polyaniline (PAni), polypyrrole (PPy) and poly (3,4-ethylenedioxythiophene) (PEDOT) as the active layers have been reviewed. This review discusses the sensing mechanism and configurations of the sensors. The factors that affect the performances of the gas sensors are also addressed. The disadvantages of the sensors and a brief prospect in this research field are discussed at the end of the review.
1,333 citations
TL;DR: The compatibility of the room‐temperature process developed herein with commonly used plastic substrates may lead to applications such as the development of large‐area flexible solar cells.
Abstract: A new method for the preparation of active layers of polymeric solar cells without the need for thermal post-treatment to obtain optimal performance is presented. Poly(3-hexylthiophene) (P3HT) nanofibers are obtained in highly concentrated solutions, which enables the fabrication of nanostructured films on various substrates. Here, the preparation of these fibers along with their characterization in solution and in the solid state is detailed. By mixing these nanofibers with a molecular acceptor such as [6,6]-phenyl C61-butyric acid methyl ester (PCBM) in solution, it is possible to obtain in a simple process a highly efficient active layer for organic solar cells with a demonstrated power conversion efficiency (PCE) of up to 3.6 %. The compatibility of the room-temperature process developed herein with commonly used plastic substrates may lead to applications such as the development of large-area flexible solar cells.
506 citations
TL;DR: In this article, the anisotropic conductivity of spin-coated poly(3,4- ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films by temperature-dependent conductivity measurements, has been analyzed.
Abstract: The anisotropic conductivity of spin-coated poly(3,4- ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films by temperature-dependent conductivity measurements, has been analyzed. A detailed 3D morphological model was derived from topographic scanning tunneling microscopy (STM) and cross-sectional atomic force microscopy (AFM) images, which correlated the anisotropy, both in conductivity magnitude and in the conduction mechanism. Spin coated films of PEDOT:PSS formed a reasonably homogenous material in terms of electrical conductivity. It was observed that the vertical conductivity that is perpendicular to the substrate, can be up to three orders of magnitude lower than the lateral conductivity in the plane of the film. The macroscopic in-plane conductivity was found to be completely isotropic, and the ordering was found to be confined to randomly oriented micrometer-size domains.
483 citations
TL;DR: Interactions between neural cells and the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) toward development of electrically conductive biomaterials intended for direct, functional contact with electrically active tissues such as the nervous system, heart, and skeletal muscle are described.
471 citations
TL;DR: In this paper, the effects of surface modification of titania (TiO2) in hybrid TiO2∕regioregular poly(3-hexylthiophene) (P3HT) photovoltaic cells were systematically investigated.
Abstract: We have systematically investigated the effects of surface modification of titania (TiO2) in hybrid TiO2∕regioregular poly(3-hexylthiophene) (P3HT) photovoltaic cells. By employing a series of para-substituted benzoic acids with varying dipoles and a series of multiply substituted benzene carboxylic acids, the energy offset at the TiO2∕polymer interface and thus the open-circuit voltage of devices can be tuned systematically by 0.25 V. Transient photovoltage measurements showed that the recombination kinetics was dominated by charge carrier concentration in these devices and were closely associated with the dark current. The saturated photocurrent of TiO2∕P3HT devices exhibited more than a twofold enhancement when molecular modifiers with large electron affinity were employed. The ability of modifiers to accept charge from polymers, as revealed in photoluminescence quenching measurement with blends of polymers, was shown to be correlated with the enhancement in device photocurrent. A planar geometry photo...
446 citations
TL;DR: In this paper, a polyaniline electrode was prepared by potentiostatic deposition of aniline on a hierarchically porous carbon monolith (HPCM), which was carbonized from the mesophase pitch.
Abstract: A high-performance polyaniline electrode was prepared by potentiostatic deposition of aniline on a hierarchically porous carbon monolith (HPCM), which was carbonized from the mesophase pitch. A capacitance value as high as 2200 F g–1 (per weight of polyaniline) is obtained at a power density of 0.47 kW kg–1 and an energy density of 300 W h kg–1. This active material deposited on HPCM also has the advantageous of high stability. These properties can be essentially attributed to the backbone role of HPCM. The method also has the advantage of a topology that is favorable for kinetics at high power densities, thus, contributing to the increase of ionic conductivity and power density. There is also no need for a binder, which not only lowers the preparation costs but also offers advantages in terms of stability and performance.
420 citations
394 citations
TL;DR: In this article, the authors illustrate possible alternative strategies based on the development of organic semiconductors with higher dimensionality, capable of exhibiting isotropic electronic properties, such as organic light-emitting diodes (OLEDs), organic field effect transistors (OFETs), or solar cells.
Abstract: Organic semiconductors based on π-conjugated systems are the focus of considerable interest in the emerging area of soft or flexible photonics and electronics. Whereas in recent years the performances of devices such as organic light-emitting diodes (OLEDs), organic field-effect transistors (OFETs), or solar cells have undergone considerable progress, a number of technical and fundamental problems related to the low dimensionality of organic semiconductors based on linear π-conjugated systems remain unsatisfactorily resolved. This low dimensionality results in an anisotropy of the optical and charge-transport properties, which in turn implies a control of the material organization/molecular orientation during or after device fabrication. Such a constraint evidently represents a problem when device fabrication by solution-based processes, such as printing techniques, is envisioned. The aim of this short Review is to illustrate possible alternative strategies based on the development of organic semiconductors with higher dimensionality, capable to exhibit isotropic electronic properties.
379 citations
TL;DR: In this paper, aniline and pyrrole have been oxidized with ammonium peroxydisulfate in aqueous solutions, in the presence of equimolar quantities of hydrochloric acid.
TL;DR: Inorganic Semiconductors for Light-emitting Diodes (E Fred Schubert, Thomas Gessmann, and Dieter Neher) as mentioned in this paper have been used in the development of organic light emitting devices (OLEDs).
Abstract: 1 Inorganic Semiconductors for Light-emitting Diodes (E Fred Schubert, Thomas Gessmann, and Jong Kyu Kim) 11 Introduction 12 Optical Emission Spectra 13 Resonant-cavity-enhanced Structures 14 Current Transport in LED Structures 15 Extraction Efficiency 16 Omnidirectional Reflectors 17 Packaging 18 Conclusion References 2 Electronic Processes at Semiconductor Polymer Heterojunctions (Arne C Morteani, Richard H Friend, and Carlos Silva) 21 Introduction 22 Charge Capture at Polymer Heterojunctions 23 Exciton Dissociation at Polymer Heterojunctions 24 Morphology-dependent Exciton Retrapping at Polymer Heterojunctions 25 Summary Acknowledgments References 3 Photophysics of Luminescent Conjugated Polymers (Dirk Hertel and Heinz Bssler) 31 Introduction 32 Spectroscopy of Singlet States 33 Optically Induced Charge Carrier Generation 34 Triplet States 35 Resum Acknowledgement References 4 Polymer-Based Light-Emitting Diodes (PLEDs) and Displays Fabricated from Arrays of PLEDs (Xiong Gong, Daniel Moses and Alan J Heeger) 41 Introduction 42 LEDs Fabricated from Semiconducting Polymers 43 Accurate Measurement of OLED/PLED Device Parameters 44 Fowler-Nordheim Tunneling in Semiconducting Polymer MIM Diodes 45 Pixilated Displays 46 Thickness Dependence of Electroluminescence Efficiency 47 Limits on the Electroluminescence Efficiency 48 White-light emission 49 Conclusion Note Acknowledgement References 5 Metal/Polymer Interface Studies for Organic Light-Emitting Devices (Man-Keung Fung, Chun-Sing Lee, and Shuit-Tong Lee) 51 Review of Organic Light-Emitting Diodes and their Fundamental Interface Studies 52 Polymer Materials, their Preparations, and Experimental Details 53 Chemistry and Electronic Properties of Metal/F8BT 54 Role of Ytterbium and Ytterbium/Cesium Fluoride on the Chemistry of F8BT 55 Highly Efficient and Substrate-Independent Ytterbium/Cesium Fluoride Cathodes 56 Conclusions Acknowledgements References 6 The Synthesis of Electroluminescent Polymers (Andrew C Grimsdale) 61 Introduction 62 Poly(arylene vinylene)s 63 Poly(arylene ethynylene)s 64 Polyarylenes 65 EL Polymers with Isolated Chromophores 66 Stability of EL Polymers 67 Conclusion References 7 Charge-transporting and Charge-blocking Amorphous Molecular Materials for Organic Light-emitting Diodes (Yasuhiko Shirota) 71 Introduction 72 Amorphous Molecular Materials 73 Requirements for Materials in OLEDs 74 Amorphous Molecular Materials for Use in OLEDs 75 Charge Transport in Amorphous Molecular Materials 76 Outlook References 8 Dendrimer Light-Emitting Diodes (John M Lupton) 81 Introduction 82 The Dendrimer Concept 83 Electroluminescent Dendritic Materials 84 Electronic Properties 85 Dendrimer Devices 86 Dendronized Polymers 87 Conclusions References 9 Crosslinkable Organic Semiconductors for Use in Organic Light-Emitting Diodes (OLEDs) (Klaus Meerholz, Christoph-David Mller, Oskar Nuyken) 91 Introduction 92 Multiple-Layer Deposition 93 Patterning 94 Conclusion and Outlook Acknowledgements References 10 Hybrid OLEDs with Semiconductor Nanocrystals (Andrey L Rogach and John M Lupton) 101 Introduction 102 LEDs in the Visible based on Composites of Semiconductor Nanocrystals and Polymers or Nanocrystals and Small Organic Molecules 103 Near-infrared LEDs based on Composites of Semiconductor Nanocrystals and Polymers or Small Organic Molecules 104 Concluding Remarks References 11 Polymer Electrophosphorescence Devices (Xiaohui Yang and Dieter Neher) 111 Introduction 112 Phosphorescent Dyes 113 Transfer Processes in Polymer Hosts Doped with Phosphorescent Dyes 114 Polymer Phosphorescence Devices based on PVK 115 Phosphorescent Devices with Other Host Polymers 116 Fully Functionalized Polymers 117 Conclusion and Outlook Acknowledgement References 12 Low-threshold Organic Semiconductor Lasers (Daniel Schneider, Uli Lemmer, Wolfgang Kowalsky, Thomas Riedl) 121 Introduction 122 Fundamentals of Organic Semiconductor Lasers 123 Low-threshold Organic Lasing 124 Comparison of Organic Laser Properties 125 Electrically Driven Organic Lasers 126 Summary and Outlook References Subject Index
TL;DR: In this paper, composites of carbon nanotubes with polyaniline (PANI), polypyrrole (PPY) or poly[3,4-ethylenedioxythiophene] (PEDOT) were prepared via electrochemical co-deposition from solutions containing acid treated CNTs and the corresponding monomer.
TL;DR: Data indicate that the incorporation of NGF can modify the biological interactions of the electrode without compromising the conductive properties or the morphology of the polymeric film.
Abstract: The use of biologically active dopants in conductive polymers allows the polymer to be tailored for specific applications. The incorporation of nerve growth factor (NGF) as a co-dopant in the electrochemical deposition of conductive polymers is evaluated for its ability to elicit specific biological interactions with neurons. The electrochemical properties of the NGF-modified conducting polymers are studied by impedance spectroscopy and cyclic voltammetry. Impedance measurements at the neurobiologically important frequency of 1 kHz reveal that the minimum impedance of the NGF-modified polypyrrole (PPy) film, 15 kX, is lower than the minimum impedance of peptide-modified PPy film (360 kX). Similar results are found with NGF-modified poly(3,4-ethylene dioxythiophene) (PEDOT). The microstructure of the conductive polymer films is characterized by optical microscopy and electron microscopy and indicates that the NGF-functionalized polymer surface topology is similar to that of the unmodified polymer film. Optical and fluorescence microscopy reveal that PC-12 (rat pheochromacytoma) cells adhered to the NGF-modified substrate and extended neurites on both PPy and PEDOT, indicating that the NGF in the polymer film is biologically active. Taken together these data indicate that the incorporation of NGF can modify the biological interactions of the electrode without compromising the conductive properties or the morphology of the polymeric film.
TL;DR: The electrochemical synthetic mechanism of conductive polymer nanotubes in a porous alumina template using poly(3,4-ethylenedioxythiophene) (PEDOT) as a model compound is investigated to uncover the detailed mechanism underlying this morphological transition between nanowire and nanotube.
Abstract: We have investigated the electrochemical synthetic mechanism of conductive polymer nanotubes in a porous alumina template using poly(3,4-ethylenedioxythiophene) (PEDOT) as a model compound. As a function of monomer concentration and potential, electropolymerization leads either to solid nanowires or to hollow nanotubes, and it is the purpose of these investigations to uncover the detailed mechanism underlying this morphological transition between nanowire and nanotube. Transmission electron microscopy was used to characterize electrochemically synthesized PEDOT nanostructures and measure the extent of their nanotubular portion quantitatively. The study on potential dependency of nanotubular portion shows that nanotubes are grown at a low oxidation potential (1.2 V vs Ag/AgCl) regardless of monomer concentration. This phenomenon is attributed to the predominance of electrochemically active sites on the annular-shape electrode at the pore bottom of a template. The explanation was supported by a further elec...
12 Dec 2007
TL;DR: Well-coated PEDot electrodes were stable under chronic stimulation conditions, suggesting that PEDOT is a promising electrode material to be further developed for chronic neural stimulation applications.
Abstract: Chronic neural stimulation using microelectrode arrays requires highly stable and biocompatible electrode materials with high charge injection capability. Conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) was electrochemically deposited on thin film Pt electrodes of stimulation electrode arrays to evaluate its properties for chronic stimulation. The coated electrodes demonstrated much lower impedance than thin film Pt due to the high surface area and high ion conductivity across the film. The PEDOT film also presents intrinsic redox activity which contributes to the low impedance as well as a much higher charge storage capacity. The charge injection limit of PEDOT electrode was found to be 2.3 mC/cm2 , comparable to IrOx and much higher than thin film Pt. Under biphasic stimulation, the coated electrodes exhibited lower voltage and linear voltage excursion. Well-coated PEDOT electrodes were stable under chronic stimulation conditions, suggesting that PEDOT is a promising electrode material to be further developed for chronic neural stimulation applications.
TL;DR: Different ionic liquids (ILs) have been used as dopants in conducting polymer aqueous dispersion (PEDOT) leading to films of PEDOT:PSS/IL with enhanced electrical conductivity.
Abstract: Different ionic liquids (ILs) have been used as dopants in conducting polymer aqueous dispersion (PEDOT:PSS) leading to films of PEDOT:PSS/IL with enhanced electrical conductivity (up to 136 S cm-1). After the addition of the ILs, AFM images of the films show a three-dimensional conducting network of highly conducting PEDOT exhibiting preferred paths for charge carrier transport.
TL;DR: Electrodes with three-dimensionally ordered macroporous (3DOM) carbon as the intermediate layer between an ionophore-doped solvent polymeric membrane and a metal contact are presented as a novel approach to solid-contact ion-selective electrodes (SC-ISEs).
Abstract: Electrodes with three-dimensionally ordered macroporous (3DOM) carbon as the intermediate layer between an ionophore-doped solvent polymeric membrane and a metal contact are presented as a novel approach to solid-contact ion-selective electrodes (SC-ISEs). Due to the well-interconnected pore and wall structure of 3DOM carbon, filling of the 3DOM pores with an electrolyte solution results in a nanostructured material that exhibits high ionic and electric conductivity. The long-term drift of freshly prepared SC-ISEs with 3DOM carbon contacts is only 11.7 μV/h, and does not increase when in contact with solution for 1 month, making this the most stable SC-ISE reported so far. The electrodes show good resistance to the interference from oxygen. Moreover, in contrast to previously reported SC-ISEs with conducting polymers as the intermediate layer, 3DOM carbon is an electron conductor rather than a semiconductor, eliminating any light interference.
TL;DR: In this paper, the authors report efficient photovoltaic diodes which use poly((9,9-dioctylfluorene)-2,7-diyl-alt-[4,7bis(3-hexylthien-5-yl]-2,1,3-benzothiadiazole]-2′,2″-diym) (F8TBT) both as electron acceptor, in blends with poly(3hexyl-thiophene), and as hole acceptor.
Abstract: The authors report efficient photovoltaic diodes which use poly((9,9-dioctylfluorene)-2,7-diyl-alt-[4,7-bis(3-hexylthien-5-yl)-2,1,3-benzothiadiazole]-2′,2″-diyl) (F8TBT) both as electron acceptor, in blends with poly(3-hexylthiophene), and as hole acceptor, in blends with (6,6)-phenyl C61-butyric acid methyl ester In both cases external quantum efficiencies of over 25% are achieved, with a power conversion efficiency of 18% under simulated sunlight for optimized F8TBT/poly(3-hexylthiophene) devices The ambipolar nature of F8TBT is also demonstrated by the operation of light-emitting F8TBT transistors The equivalent p- and n-type operation in this conjugated polymer represent an important extension of the range of useful n-type materials which may be developed
TL;DR: In this paper, an approach for preparing a free-standing ACNT/PEDOT/PVDF membrane electrode that is lightweight, flexible, highly electroactive and conductive, and mechanically robust is presented.
Abstract: We present here an approach for preparing a nanostructured “free-standing” ACNT/PEDOT/PVDF membrane electrode that is lightweight, flexible, highly electroactive and conductive, and mechanically robust. It could be directly and easily fabricated into a rechargeable lithium-ion battery as the anode material without using a metal substrate or binder.
TL;DR: In this paper, the electrical conductivity of poly(3,4-ethylenedioxythiophene) (PEDOT) was achieved by oxidative chemical vapor deposition (oCVD).
Abstract: Systematic variation in the electrical conductivity of poly(3,4-ethylenedioxythiophene) (PEDOT) was achieved by oxidative chemical vapor deposition (oCVD). For oCVD, both the oxidant, Fe(III)Cl 3 , and 3,4-ethylenedioxythiophene (EDOT) monomer are introduced in the vapor phase. A heated crucible allows for sublimation of the oxidant directly into the reactor chamber operating at 150 mTorr. Spontaneous reaction of the oxidant with the monomer introduced though a feedback-controlled mass flow system results in the rapid (>200 nm thick film in 30 min) formation of π-conjugated PEDOT thin films directly onto a temperature-controlled substrate. As the substrate temperature is increased from 15 to 110 °C, increasing conjugation length, doping level, and electrical conductivity of the PEDOT chains are observed by UV-vis absorption spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy. Concomitantly, the measured electrical conductivity of the PEDOT films increases systematically with an apparent activation energy of 28.2 ±1.1 kcal/mol.
TL;DR: In this paper, in situ polymerization of polypyrrole on carbon nanotubes in 01-M HCl containing (NH 4 )S 2 O 8 as oxidizing agent over a temperature range of 0-5°C Pt nanoparticles are deposited on PPy-CNT composite films by chemical reduction of H 2 PtCl 6 using HCHO as reducing agent at pH = pH 11 [Pt/PPy−CNT].
TL;DR: In this paper, the dielectric and electrical properties of PANI/epoxy composites were studied for samples in parallel plate configuration, and the distribution of the conductive element clusters within the polymer matrix was studied by SEM and correlated to the polyaniline behavior of the composite films.
TL;DR: In this article, multiple regioregular polythiophene polymers with a variety of side chains, end groups and secondary polymer chains were used as active sensing layers in a single chip chemresistor sensor array device.
Abstract: Multiple regioregular polythiophene polymers with a variety of side chains, end groups and secondary polymer chains were used as active sensing layers in a single chip chemresistor sensor array device A custom inkjet system was used to selectively deposit the polymers onto the array of transduction electrodes The sensor demonstrated sensitivity and selectivity for detection and discrimination of volatile organic compounds (VOCs) The conductivity responses to VOC vapors are dependent on the chemical structure of the polymers For certain VOCs, conductivity increased in some polymers, while it decreased in others Principal component analysis (PCA) of sensor responses was used to discriminate between the tested VOCs These results are correlated to the chemical structures of the different polymers, and qualitative hypothesis of chemical sensing mechanisms are proposed This research demonstrates the potential for using such devices in VOC detection and discrimination sensing applications
TL;DR: In this article, a highly elastic and stretchable conductive poly(3,4-ethylenedioxythiophene):p-tosylate and an aliphatic polyurethane elastomer.
Abstract: A highly elastic and stretchable conductive polymer material resulted from blending the conductive polymer poly(3,4-ethylenedioxythiophene):p-tosylate and an aliphatic polyurethane elastomer. The blend inherited advantageous properties from its constituents, namely high conductivity of 120 S cm–1 from its conductive polymer component, and elastomeric mechanical properties resembling those of the polyurethane, including good adhesion to various substrates. Stretching of the blend material by up to 50 % resulted in increased conductivity, while subsequent relaxation to the unstretched state caused a decrease of conductivity compared to the pristine blend. These initial changes in conductivity were reproducible on further cycling between 50 % stretching and the unstretched state for at least 10 cycles. Stretching beyond 50 % resulted in decreasing conductivity of the blend but with substantial conductivity remaining even when stretched by 200 %. Optical, mechanical, and thermal properties of the blend, as well as high resolution electron microscopy of bulk cross-sections, suggest that the system is a single phase and not two separate phases. Ageing experiments indicate that the material retains substantial conductivity for at least a few years at room temperature.
TL;DR: In this article, the electrochemical capacitance properties of composite films prepared from electrically conducting polypyrrole (PPy) and single wall carbon nanotubes (SWNTs) have been investigated for supercapacitor application.
TL;DR: In this article, the effect of doping ions on the photo-electron conversion performance in dye-sensitized solar cells was investigated and showed that the interaction between polymer and substrate (FTO) directly influences the fill factor in I-V curves, especially in the PEDOT-PSS system.
Abstract: Poly(3,4-ethylenedioxythiophene) (PEDOT) is an excellent kind of conducting polymer, comparable to Pt in catalytic behavior in dye-sensitized solar cells. Electrochemical polymerization in the presence of different anions (doping ions) that work as counterions of the resulting oxidized state PEDOT has been carried out to verify the influence of doping ions on the photo-electron conversion performance in dye-sensitized solar cells. Electrochemical and photo-electrochemical measurements reveal that the interaction between polymer and substrate (FTO) directly influences the fill factor in I–V curves, especially in the PEDOT–PSS system.