Electrical and optical properties of pure and KClO3-doped P(MMA-CO-4VPNO) polymer electrolyte films

Ion-conducting polymer electrolyte films based on a copolymer poly(methyl-methacrylate-co-4-vinyl pyridine N-oxide) [P(MMA-CO-4VPNO)] complexed with potassium chlorate (KClO3) were prepared by solution cast technique. The complexation of KClO3 salt with the polymer was confirmed by X-ray diffraction and infrared studies. The electrical conductivity and optical absorption of pure and KClO3-doped P(MMA-CO-4VPNO) polymer electrolyte films have been studied. The electrical conductivity increased with increasing dopant concentration, which is attributed to the formation of charge transfer complexes. The variation of electrical conductivity with temperature shows two regions with two activation energies. Optical properties like direct band gap, indirect band gap, and optical absorption edge were investigated for pure and doped polymer films in the wavelength range 300-550 nm. It was found that the energy gaps and band edge values shifted to lower energies on doping. The behavior is in an agreement with the activation energies obtained from the conductivity data.