FTIR, conductivity and ionic transport study of chitosan doped glycolic acid solid polymer electrolyte as proton conductor for battery application

Abstract

Films of chitosan- based polymer electrolyte were prepared by technique of solution casting. Fourier Transform Infrared (FTIR) Spectroscopy show that the complexation has occurred. FTIR exhibit shifts in amine bands from 1553 cm-1 to a higher wavenumber due to the increment of glycolic acid salt concentration. The effects of addition of glycolic acid on the conductivity, O" and transport properties of chitosan acetate-glycolic acid have been investigated. The highest room temperature conductivity achieved in the chitosan acetate- glycolic acid is 2.97x 10-8 S cm-1. The transference number measurement was performed to correlate the diffusion phenomena to the conductivity behavior of CA-GA polymer electrolyte. The cation transference numbers, t+, in the electrolytes were determined by monitoring the current as a function of time on application of a fixed de voltage (1.5 V) across the sample sandwiched between two stainless steel electrodes. The conductivity, O" was found to be controlled by the mobility,µ and the diffusion coefficient, D. The value of µ+ and D+ is higher thanµ_ and D_ which implies that the CA-GA polymer is a proton conductor.