Structural, thermal and electrochemical characterization of cellulose acetate-based solid biopolymer electrolyte for zinc ion batteries

Zinc ion conducting biopolymer electrolyte has been prepared from cellulose acetate (CA) with different concentrations of zinc nitrate (Zn(NO3)(2)) by solution casting technique. The X-ray diffraction (XRD) analysis has been adopted to investigate the amorphous nature of the samples. The complex creation of the biopolymer with the inorganic salt has been evidenced by Fourier transform infrared spectroscopy (FTIR) studies. The differential scanning calorimetry (DSC) study shows shifting of glass transition temperature to the lower temperature in the salt-doped system. The polymer electrolytes have been subjected to electrochemical impedance spectroscopy (EIS), and the optimum conductivity attained was 2.7 x 10(-3) S cm(-1) for the sample with the composition 45 M.wt% CA:55 M.wt% Zn(NO3)(2). The linear sweep voltammetry (LSV) study reveals the electrochemical stability of the electrolyte as 3.03 V. The transference number for Zn2+ has been found to be 0.45 by Evans polarisation technique. The primary zinc battery has been constructed using optimum conducting membrane as an electrolyte. The OCV has been measured for this constructed battery and the value was found to be 1.72 V.

Automated summary

A zinc ion conducting biopolymer electrolyte was prepared using cellulose acetate and zinc nitrate. Various tests were conducted to study the characteristics of the electrolyte, including amorphous nature, complex creation, and conductivity. A primary zinc battery was constructed and the open circuit voltage was measured.