Electrochemical characterization of NaClO4–mixed rice starch as a cost-effective and environment-friendly electrolyte

Abstract

Being eco-friendly, cost-effective, easy to synthesize and handle, starch-based electrolytes have tremendous advantages for electrochemical device fabrications. Starch electrolytes synthesized by crosslinking process result in stable, flexible, free-standing films which can be molded in different shapes and sizes. Rice starch–based material, prepared using glutaraldehyde as crosslinker and NaClO4 as ion-providing salt, resulted in high conductivity (~ 0.01 S/cm) and fast-relaxing (ion relaxation time in micro seconds) electrolytes having wide electrochemical stability window (~ 3 V). Resistance of highest conducting sample, having 0.8 mm thickness and 1 × 1 cm2 area is ~ 6 Ω. The synthesized electrolyte is easily moldable in desired shape and size and hence devices may be fabricated with smaller equivalent series resistance. The estimated relaxation time is 62 μs indicating that fabricated devices will be able to deliver energy in shorter time. The approximate preparation cost of the material (1 × 1 × 0.08 cm3) is INR 20 (~ 0.3USD). The low cost, good technical parameters, and flexibility make it a promising material for electrochemical device fabrication.