Corn silk extract–based solid-state biopolymer electrolyte and its application to electrochemical storage devices

A solid-state biopolymer electrolyte was prepared from the biomaterial Corn Silk Extract (CSE) by blending with polyvinyl alcohol and different concentration of MgCl2 by opting solution casting technique. The maximum ionic conductivity of 1.74 × 10−5 Scm−1 for the blend pure biopolymer (0.9 g CSE + 1 g PVA) and 1.28 × 10−3 Scm−1 for the biopolymer electrolyte was obtained from the AC Impedance analysis. The obtained biopolymer electrolyte is characterized by Fourier transform infrared spectroscopy to look into the complex formation of the biopolymer blend and the salt. The maximum amorphous nature has been observed for 0.9 g CSE + 1 g PVA + 0.45wt% MgCl2 by the XRD technique. Glass transition temperature of the biopolymer electrolyte was found by the differential scanning calorimetry (DSC) process. The electrochemical potential window of the biopolymer electrolyte with maximum conductivity is obtained as 2.65 V in linear sweep voltammetry (LSV). The transference number is calculated from Wagner’s and Evan’s polarization techniques. A primary Mg-ion battery is constructed with an open-circuit voltage of 1.95 V at room temperature.