Preparation of polyethylene oxide composite electrolytes containing imidazolium cation salt-attached titanium oxides and their conducing behavior

We report an addition effect of imidazolium salt modified filler (IS-TiO₂), which is successfully prepared by sol-gel process and incorporated in poly(ethylene oxide) (PEO) based nanocomposite polymer electrolytes (NCPE). In order to ascertain the thermal and crystalline properties of NCPE with maximum conductivity, films were subjected to differential scanning calorimeter (DSC) analysis. The crystallinity of the NCPE was evaluated using X-ray diffraction (XRD) and the ionic conductivity was measured by AC impedance method. Ionic conductivites of NCPE containing TiO₂ or IS-TiO₂ are examined as a function of temperature. FT-IR spectroscopy is used to study polymer structure and interactions between PEO chain and filler, which can make changes in the force constant of CO groups. The morphology of CPE was analyzed by SEM method. Owing to the presence of imidazolium salt attached on titanium oxide, the beneficial effects were obtained such as the better dispersion and lower interfacial resistance of polymer electrolytes. In accordance with these reasons, the NCPE containing the imidazolium salt modified filler shows slightly higher ionic conductivity than the NCPE containing the pure TiO₂.