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This study represented a novel conducting poly (p-nitroaniline-co-p-aminophenol) (P(p-NAn-co-p-APh)) material, obtained by electrocopolymerization of para-nitroaniline (p-NAn) and para-aminophenol (p-APh) in aqueous sulfuric acid solution. Copolymerization was carried out using cyclic voltammetry technique on gold electrode with different monomer feed concentrations. The obtained polymer and copolymer films had been characterized by scanning electron microscopy (SEM), in situ conductivity measurements, in situ UV-Vis, and FT-IR spectroscopy. Initial cyclic voltammograms of p-NAn, p-APh and p-NAn + p-APh showed that the peak potentials were located at different values. The in situ conductivity of the copolymers measured between -0.20 V< Esce< 0.70 V increased with decreasing the [p-NAn]/[p-APh] concentration ratio. In situ UV-Vis. spectra of the obtained samples revealed strong absorption bands at different applied potentials and wavelengths. The structure and morphology characterizations of homo and copolymer films were studied by FT-IR spectroscopy and SEM analysis. Fundamental differences between the morphology of the homo- and copolymers were observed. The mechanism of the electrochemical copolymerization reaction was discussed as well. [ABSTRACT FROM AUTHOR]

In this work, we presented a novel conducting poly ( p -nitroaniline-co- N -methylaniline) (P( p -NAn-co-NMAn)) material, obtained by electrocopolymerization of para -nitro aniline ( p -NAn) and N -methyl aniline (NMAn) in aqueous sulfuric acid solution. The purposes of this research are investigation and characterization properties of synthesized copolymers and investigation of catalytic effect of NMAn on the polymerization of para-nitro aniline. Electrosynthesis was carried out using cyclic voltammetry technique with different monomer feed concentrations. Characterization of samples were carried out by cyclic voltammetry, in situ conductivity measurements, scanning electron microscopy (SEM), in situ UV–vis, and FT-IR spectroscopy techniques. The cyclic voltammograms of P( p -NAn), P(NMAn) and P( p -NAn-co-NMAn) showed that the peak potentials were located at different values due to different monomer concentration employed during the electrosynthesis process. The in situ conductivity of the p -NAn-co-NMAn increased with increasing the [ p -NAn]/[NMAn] concentration ratios. Mechanisms of polymerization and copolymerization reactions of homo and copolymers were suggested. The in situ UV–vis. spectroscopy results revealed strong absorption bands at different applied potentials and a spectroscopic behavior of copolymers intermediate between that of the homopolymers. The FT-IR spectroscopy and SEM analysis results showed the fundamental differences between the structures and morphology of the homo- and copolymers. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) and polypyrrole-based gamma aluminum oxide (γ-Al 2 O 3 ) and gamma iron (III) oxide (γ-Fe 2 O 3 ) nanocomposites were synthesized via in situ electropolymerization methods Films were characterized via cyclic voltammetry (CV) and in situ spectroelectrochemistry methods such as in situ UV–Visible spectroscopy and in situ conductivity measurements. Polymer nanocomposite structures and morphologies were studied and characterized via Fourier transform infrared (FT-IR) spectroscopy, electrochemical impedance spectroscopy (EIS), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). According to the CV results of the nanocomposites, the separation of anodic and cathodic peak potential of the redox couples (ΔE) exhibited good reversibility with a positive potential shift compared with PPy during redox sweeps. The electrochemical properties of PPy, PPy/γ-Fe 2 O 3, and PPy/γ-Al 2 O 3 nanocomposite electrodes in a solution of H 2 SO 4 were studied via CV, galvanostatic charge–discharge, and EIS measurements to understand the pseudocapacitance that formed due to oxidation and reduction reactions over the double layer capacitance. Results for the nanocomposites revealed that they were very good candidates for supercapacitor applications, with higher specific capacitances, cyclic self-stabilities, and better rate capabilities than those of PPy films. The specific capacitance values of PPy/γ-Fe 2 O 3 (106 F/g) and PPy/γ-Al 2 O 3 (92 F/g) nanocomposites based on a three-electrode cell configuration from galvanostatic charge–discharge at a constant current density of 1 A/g were higher than that for PPy (75 F/g). [ABSTRACT FROM AUTHOR]