Substantial ion conduction in the biopolymer membrane: Efficacy of NaI on sodium alginate matrix

Water-soluble sodium alginate-based biopolymer electrolyte membranes integrated with NaI have been prepared by solution cast route and analyzed in terms of its complexation, degree of crystallinity, glass transition temperature and ionic conductivity. With the increasing concentration of NaI in the biopolymer matrix, the amorphous phase becomes prominent besides NaI content changes the transition temperature values and the ionic conductivity. The membrane can fetch high ionic conductivity in the order of 10⁻² S cm⁻¹. The present study lays the groundwork for scrutinizing the optimal concentration for obtaining high ion conductive membranes which are favorable for all solid batteries.