Ion Dynamics Study of Potato Starch + Sodium Salts Electrolyte System

The effect of different anions, namely, , , and , on the electrical properties of starch-based polymer electrolytes has been studied. Anion size and conductivity are having an inverse trend indicating systems to be predominantly anionic conductor. Impact of anion size and multiplet forming tendency is reflected in number of charge carriers and mobility, respectively. Ion dynamics study reveals the presence of different mechanisms in different frequency ranges. Interestingly, superlinear power law (SLPL) is found to be present at <5？MHz frequency, which is further confirmed by dielectric data. 1. Introduction Potentiality of polymer electrolytes was first recognized by Armand et al. [1]. Since then, extensive work has been carried out in the field resulting in further subdivision of field into different branches, such as gelled polymer electrolyte, polymer-salt complex electrolyte, and composite polymer electrolyte. Biopolymer-based polymer-salt complex electrolytes are relatively new class of material and serving as environment friendly alternates to their synthetic counter parts [2, 3]. Among the biopolymers-based polymer-salt complexes, starch-based materials are gaining much recognition. Many leading groups [4–8] are working in the field. A review of natural polysaccharides as electroactive polymers by Finkenstadt summarizes the basics and importance of starch-based electrolytes [4]. Conductivity up to 10？1.6？S/cm is reported by Ning et al. using ionic liquid as a plasticizer in starch-based polymer electrolytes [8]. Most of the reports on the starch-based electrolytes deals only with the electrical properties of system. This motivated us to understand the ion dynamics in these systems. Earlier we have studied potato starch-based electrolyte systems having iodide anion for two different cations [9, 10] which exhibited good electrolytic nature. Now, we extended our study to comprehend the effect of different anion in starch-based polymer-salt complexes. , , and anions are known for making polymer-salt complexes with synthetic polymers. Hence, in present paper, we are reporting starch-based electrolyte systems prepared by doping starch with sodium salt of these anions. Prepared system’s electrical behavior is analyzed using Impedance spectroscopy and by representing the impedance data in different formalism, namely, dielectric, modulus and conductivity. The use of conductivity formalism to investigate the dynamics of charge carrier is quite admired because of its simplicity. In 1977, Jonscher proposed “Universal dielectric response” to deal with