Investigation of hydrogen ion transport in NH4HCO2 doped TSP biopolymer electrolyte for battery applications

Abstract

Unique proton conducting biopolymer membrane containing Tamarind seed polysaccharide (TSP), Ammonium formate (NH4HCO2) was prepared and investigated in the present work. The addition of NH4HCO2 increases the ionic conductivity of TSP biopolymer by four orders of magnitude from 5.48 × 10-7 S cm−1 to 1.23 × 10-3 S cm−1. The relative percentage of free ions, contact pairs and contract pairs was calculated by deconvoluting FTIR spectrum. Transference number measurement (TNM) indicates that the conducting species are predominantly H+ ions. The electrochemical stability window of 3 V was observed for the highest conducting sample by LSV.