Materials and ion transport property studies on hot-press casted solid polymer electrolyte membranes: [(1 − x) PEO: x KIO 3

Abstract

Materials and ion transport property characterization in Solid Polymer Electrolyte (SPE) membranes: (1 − x) PEO: x KIO 3, where x = 0, 10, 20, 30, 40, 50 wt.%, have been studied. SPE films have been prepared following two casting techniques: a novel hot-press (extrusion) and the traditional solution cast. Hot-press technique is a completely dry/solvent free/rapid/inexpensive procedure as compared to solution cast method and has recently been receiving wider acceptability to cast membranes of ion conducting polymeric electrolytes. ‘Log σ − x’ study revealed σ-maxima at salt concentration x = 30 wt.% for SPE film prepared by both the methods. However, hot-pressed SPE film: 70 PEO: 30 KIO 3 exhibited relatively higher room temperature conductivity ( σ ∼ 4.40 × 10 − 7 S cm − 1 ) than that of the solution casted film. This has been referred to as Optimum Conducting Composition (OCC) SPE film. Materials characterization in OCC SPE film has been done by XRD, FTIR and DSC techniques. These studies confirmed the complexation of salt in the polymeric host. Some basic ionic parameters viz. conductivity ( σ), ionic mobility (μ), mobile ion concentration (n), ionic transference number (t ion) have been determined using different experimental procedures to understand the ion transport behaviour in OCC SPE material. The temperature dependent conductivity measurement has also been carried out and the activation energy (E a) has been computed from the linear least square fitting of ‘log σ − 1 / T’ Arrhenius plot.