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Electrochemical synthesis, in situ spectroelectrochemistry of conducting polyindole (PIn), polyindole-TiO 2 (PIn-TiO 2 ) and polyindole-ZnO (PIn-ZnO) nanocomposites were investigated. The PIn and polymer nanocomposites were tested electrochemically for rechargeable batteries. The films were characterized by means of CVs, in situ UV-visible, FT-IR spectroscopies, in situ resistivity measurements, energy dispersive X-ray (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The charge-discharging behavior of a Zn/1 M ZnSO 4 /PIn cell with a capacity of around 90 Ah Kg −1 and on open circuit potential of around 1.45 V was compared with Zn/1 M ZnSO 4 /PIn-nanocomposite. The potential differences of redox couples (ΔE) for nanocomposites films show very good reversibility. A positive shift of potential was observed for polymer nanocomposites during redox scan. A significant variability was observed for in situ conductivity of the PIn and polymer nanocomposites. During in situ UV-visible and FT-IR measurements, intermediate spectroscopic behavior and positive shifts of wavelengths were observed for PIn and polymer nanocomposites. The SEM, TEM and EDX of nanocomposite films show the presence of nano particle in PIn. [ABSTRACT FROM AUTHOR]

Two novel conducting polyindole (PIn) based on γ‐Fe2O3 and γ‐Al2O3 nanocomposites with LiClO4 on Au electrode (Au/PIn/ ClO4−@γ‐Al2O3 and Au/PIn/ ClO4−@γ‐Fe2O3) as cathode materials for lithium‐ion rechargeable batteries were fabricated via an in situ electropolymerization approach. The PIn and polymer nanocomposites were characterized by FT‐IR, SEM, TEM, EDX, and TGA. The electrochemical properties of PIn and polymer nanocomposites were studied by cyclic voltammetry (CV), in situ conductivity measurements, electrochemical impedance spectroscopy and charge–discharging test. The optical properties of the samples were also investigated by in situ UV‐Visible spectroscopy. The CV results show better reversibility for polymer nanocomposites in compered PIn. The intermolecular interaction between nanoparticles and PIn were confirmed by FT‐IR. The TEM images of polymer nanocomposites show that γ‐Fe2O3 and γ‐Al2O3 are embedded in PIn matrix. The thermal stability of the polymer nanocomposites has increased compared to that of PIn. The in situ conductivity of polymer nanocomposites were increased at about 0.20 order of magnitudes in compared to PIn. The electrochemical properties and charge–discharging behavior of the materials were measured with Li/LiClO4+ACN/Au‐PIn, Li/LiClO4+ACN/Au‐PIn‐γ‐Al2O3, and Li/LiClO4+ACN/Au‐PIn‐γ‐Fe2O3 cells using a constant current of 0.5 mA/cm2. The results for polymer nanocomposites cells indicated better discharging characteristics at about 116–124 mAh/g with very good cyclic properties in compered to PIn cell. The discharge capacities achieve the best value after 30–40 cycles with around drops 3–6% after 20,000 times. POLYM. COMPOS., 40:496–505, 2019. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

We introduce high-performance polyaniline (PANI) nanocomposite supercapacitors based on gamma aluminum oxide (γ-Al 2 O 3 ) and gamma iron (III) oxide (γ-Fe 2 O 3 ) nanoparticles with a high specific surface area. PANI and its polymer nanocomposites are synthesized via in situ electropolymerization on gold electrodes. The structures and morphologies are characterized by cyclic voltammetry, FT-IR spectroscopy, SEM, TEM, and EDX. The electrochemical properties and specific surface area of the electrodes are investigated by galvanostatic charge–discharge, electrochemical impedance spectroscopy (EIS) and BET theory. The enhanced specific capacitance with higher surface area and conductivities is observed in PANI/γ-Fe 2 O 3 (342 F/g), PANI/γ-Al 2 O 3 (292 F/g) and PANI (180 F/g) electrodes with a constant current density of 1A/g. The cyclic performance of the PANI electrodes following 8000 cycles of operations were at 87% (PANI), 91% (PANI/γ-Al 2 O 3 ), and 93% (PANI/γ-Fe 2 O 3 ) of their initial capacitance. In addition, higher specific capacitances, higher conductivity and cyclic self-stabilities observed for the PANI/nanocomposite electrodes can provide new opportunities in the field of energy storage and supercapacitor applications. [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]