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Ion-conducting solid polymer blend electrolytes based on polyvinyl chloride (PVC)/poly methyl methacrylate (PMMA) complexed with sodium perchlorate (NaClO 4 ) were prepared in various concentrations by solution cast technique. The features of complexation of the electrolytes were studied by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. DC conductivity of the films was measured in the temperature range 303-398 K. Transference number measurements were carried out to investigate the nature of charge transport in the polymer blend electrolyte system. The electrical conductivity increased with increasing dopant concentration, which is attributed to the formation of charge transfer complexes. The polymer complexes exhibited Arrhenius type dependence of conductivity with temperature. In the temperature range studied, two regions with different activation energies were observed. Transference number data showed that the charge transport in this system is predominantly due to ions. Optical properties like absorption edge, direct band gap, and indirect band gap were estimated for pure and doped films from their optical absorption spectra in the wavelength region 200-600 nm. It was found that the energy gap and band edge values shifted to lower energies on doping with NaClO 4 salt.

A solid polymer blend electrolyte system based on polyvinyl alcohol (PVA) and polyethylene glycol (PEG) complexed with NaClO 4 was prepared using solution cast technique. The structural properties of these electrolyte films were examined by X-ray diffractrometry (XRD) studies. The XRD data revealed that the amorphous domains of polymer blend matrix increased with increase of sodium salt concentration. The complexation of the salt with the polymer blend was confirmed by Fourier transform infrared (FTIR) studies. DC conductivity of the films was measured in the temperature range 303-398 K. The electrical conductivity increased with increasing dopant concentration, which is attributed to the formation of charge transfer complexes. The electrolyte exhibited the highest room temperature conductivity 2.41× 10 −6 S cm −1 at 30 % of NaClO 4 salt concentration. The polymer complexes exhibited Arrhenius-type dependence of conductivity with temperature. In the temperature range studied, two regions with different activation energies were observed. Electrochemical cells of configuration Na/(PVA+ PEG+NaClO 4 )/(I 2 +C+electrolyte) were fabricated and the discharge characteristics of these cells were studied under a constant load of 100 K. Several cell parameters associated with the cells were evaluated and compared with earlier reports. UV-VIS absorption spectra in wavelength region 200-600 nm were used to evaluate the optical properties like direct band gap, indirect band gap and absorption edge. The optical band gaps decreased with increasing sodium ion concentration. This suggests that NaClO 4 is a good dopant to improve the electrical properties of PVA + PEG polymer blend electrolytes.

This paper presents results of studies on dc electrical conductivity and transference number measurements on potassium bromate (KBrO 3 ) complexed polyvinyl chloride (PVC) films prepared by solution cast technique. Temperature dependence of dc electrical conductivity and transference number data indicated the dominance of ion type charge transport in these specimens. The magnitude of conductivity increased with increase in concentration of the salt and temperature. Using this (PVC+KBrO 3 ) electrolyte, solidstate electrochemical cells were fabricated, and their discharge profiles were studied under a constant load of 100 kΩ. Several cell profiles such as open circuit voltage, short circuit current, power density, and energy density associated with these cells were evaluated and were reported. The features of complexation of the electrolytes were studied by X-ray diffraction and Fourier transform infrared spectroscopy.

Solid polymer blend films based on polyethylene oxide and polyvinyl acetate (PVAc) were prepared in various concentrations by solution cast technique. The features of complexation of the blend films were studied by X-ray diffraction. The electrical conductivity of films was found to increase with increasing PVAc concentration. The conductivitytemperature plots were found to follow Arrhenius nature and showed a decrease in activation energy with increasing PVAc concentration. Optical properties like absorption edge and direct and indirect band gaps were estimated for pure and blend films from their optical absorption spectra. It was found that the energy gap and band edge values shifted to lower energies on blending with PVAc.