Papers by Keyword: Conducting Polymer

Abstract: We report on optimization of bar coating method for preparation of PEDOT/PSS thin films with large area on poly (ethylene terephthalate) (PET) substrates, by investigating various coating parameters in terms of sheet resistance (R_s) and transparency (T). As a result, we have found that the addition of 1 wt% Capstone FS-30, 7 wt% ethylene glycol (EG), and a motor rotation speed of 100.8 rpm, as well as a heat temperature of 120 °C is the optimum coating condition to obtain high-performance PEDOT/PSS thin films with large area whose sheet resistance (R_s) and transmittance at 550 nm (T) were 230 Ω sq^-1 and 84%,respectively.

Abstract: Polyaniline (PAni) Nanocomposites Containinganiline (Ani) Monomer and Hexanoic Acid (HA) Dopant were Successfullysynthesized by Using Chemical Oxidation Method. Titanium Dioxide (TiO₂)and Different Dimension of Multiwall Carbon Nanotubes (MWNT) Have been Added Inorder to Improve the Dielectric Permeability and Magnetic Permittivityproperties of the Pani Nanocomposites. Fourier Transform Infrared (FTIR) Andultraviolet-Visible (UV-Vis) Spectra Confirmed the Chemical Structure of Paninanocomposites. Conductivity and Magnetization Behavior were Investigated Byresistivity Meter and Vibrating Sample Magnetometer (VSM). Microwave Absorptionstudies were Carried out by Microwave Vector Network Analyzer (MVNA) from 0.5to 18 Ghz. among all the Pani Nanocomposites, Pani Nanocomposites with MWNT (D = 10-2- Nm, l = 5-15 μm) Shows Agood Reflection Loss (RL = -58 Db) at 7 Ghz with a Sharp and Narrow Peak due Tohigher Values of Magnetization (0.074 Emu/g) Andmoderate Electrical Conductivity (1.11 x 10^-2 S/cm)

Abstract: In this paper, we have reported a theoretical study of the geometric and electronic structures of EDOT:SS oligomers based on semi-empirical Austin model1 (AM1) method and density functional theory at B3LYP/3-21G* level. The effects of polymer chain length of both EDOT and SS on structural and electronic properties including bond length, bond angle, binding distance, charge, the highest occupied orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), and energy gap have been studied from the optimized oligomers which were built by varying repeating unit of monomer as n = 1, 2, 3 and 4. The results show that AM1 is not appropriate for geometry optimization of EDOT:SS system comparing to B3LYP/3-21G* level. The binding distance between H atom on EDOT and O atom on SS tends to close together with the average distance of 2.21 Å. The most positive charges locate at sulfur atoms on EDOT and EDOT:SS. The electrical conductivity of EDOT, SS and EDOT:SS increases when polymer chain is extended.

Abstract: An array of chemiresistors based on conducting polymers was assembled for the differentiation of VCO. The chemiresistor sensors were fabricated through the potentiostatic electrodeposition of polyaniline, polypyrrole and poly (3-methylthiophene) on the gap separating two planar gold electrodes set on a Teflon substrate. The electrical resistance of the sensors were measured and observed to change when exposed to the headspace of oil samples. The sensor response was rapid and exhibited good reversibility and reproducibility. Different signals were obtained for each coconut oil sample and pattern recognition techniques were employed for the analysis of the data. The developed E-nose system was able to discriminate VCO from refined, bleached and deodorized coconut oil (RBDCO) and rancid VCO.

Abstract: In this article, brief introduction and mechanism of electrochemical capacitors are revised. The main features of electrochemical capacitors and batteries about electrical energy storage devices are also compared. It is well known that various types of materials (organic, inorganic, organic-inorganic composites and organic/organic composites) are being used as electrochemical capacitors. A vast literature is available on the preparation, properties and applications of electrochemical capacitors. In this communication, important aspects related to the synthesis and evaluation of organic electrodes for use in electrochemical capacitors is encapsulated.

Abstract: Nanoparticles synthesized in various ionic liquids (ILs) were immobilized by electrophoretic deposition (EPD) at the surface of a gas sensor made of thin polyaniline (PAni) film. We used pulsed DC voltage to overcome electrochemical treatment in IL-based electrolytes. In spite that EPD is commonly used for synthesis of nanoparticle films or coatings, here we just functionalized the surface of PAni by scattered nanoparticles. Immobilized nanoparticles were observed by SEM imaging and dynamic responses of gas sensors functionalized by different nanoparticles (Ni, Ni-Fe and Ag-Cu) were compared. Using the EPD technique, sensitivity or selectivity of a gas sensor based on PAni can be improved easily.

Abstract: To date gel and film type polymer electrolytes have been widely synthesized due to their wide range of electrical properties. However, these types of polymer electrolytes exhibit poor mechanical stability and poor electrode-electrolyte contact hence deprive the overall performance of a battery system. Therefore, in order to indulge the advantages of polymer as electrolyte, a new class of liquid-type polymer electrolyte was synthesized and investigated. To date this type of polymer electrolytre has not been extensively studied. This is due to the unavailability of liquid polymer for significance application. In this study, liquid poly (methyl methacrylate) (PMMA) electrolyte was synthesized using the simplest free radical polymerization technique using benzoyl peroxide as the initiator. It was found that this liquid PMMA oligomer has potential as electrolyte in proton battery when doped with small volume of various molarity of hydrochloric acid (HCl) in which the highest ionic conductivity achieved was 10^-7 S/cm at room temperature. The properties of this liquid PMMA oligomer were further investigated using Fourier Transform Infrared Spectroscopy (FTIR).

Abstract: The evolution of the working potential, or that of the consumed electrical energy, of electrochemical artificial muscles based on electroactive materials (intrinsically conducting polymers, redox polymers, carbon nanotubes, fullerene derivatives, grapheme derivatives, porphyrines, phtalocianines, among others) and driven by constant currents senses, while working, any variation of the mechanical (trailed mass, obstacles, pressure, strain or stress) thermal or chemical conditions of work. One physically uniform artificial muscle includes one chemical motor and several chemical sensors working simultaneously under the same driving reaction. They fulfil the old dream of engineer and robot designers: one motor sensing by itself the working conditions. From basic polymeric, mechanical and electrochemical principles a basic equation is attained. It includes and describes, simultaneously, the polymeric motor characteristics (rate of the muscle movement and muscle position) and the working variables (temperature, electrolyte concentration and mechanical conditions). By changing working conditions experimental results overlap theoretical predictions. The ensemble computer-generator-muscle-theoretical equation constitutes and describes artificial mechanical, thermal and chemical proprioception (consciousness) of the system.

Abstract: In this paper, we report a one-pot method to prepare a new type of UV-curable Au/PEDOT nanocomposite used in printed electronics, which use an amphiphilic polymer polystyrenesulfonate-alt-[maleic anhydride-g-(2-hydroxy-ethyl-methacrylate)] (PSMH) as a conductive ink. The synthesis included the reduction of chloroauric acid using EDOT (3, 4-Ethylenedioxythiophene).PSMH acted a dopant for PEDOT and a stabilizer of Au nanoparticles due to the ligand exchange between chloroauric acid and carboxylate group. The carbon-carbon double bonds have been introduced into this ink with UV-curable property to enhance the water resistance of this nanocomposite before inkjet-printing. The particle size of this nanocomposite is above 200 nm while the gold particles size is above 3~10 nm. This UV-curable Au/PEDOT nanocomposite can be used as a conductive ink for inkjet printing.

Abstract: This work aims to enhance the power conversion efficiency of PEDOT:PSS/Si hybrid solar cells by reducing the resistance of PEDOT:PSS of hybrid solar cells using simple solvent treatment. A noticeable decrease in resistance of PEDOT:PSS layer was found after treating with DMSO and methanol using the dipping method or the mixing method. The combinations of these two methods allow us to greatly enhance the fill factor and power conversion efficiency of hybrid solar cells due to the significant reduction in R_s.