Deep Eutectic Solvent-Based Polymer Electrolyte Films for an Electrochemical Double Layer Cell

Abstract

Polymer electrolyte films based on DES were prepared with the solution cast technique. DES(ChCl-glycerol) was prepared with two different glycerols: one purchased from the industry and the other fabricated in the lab from waste vegetable oil. Two polymer electrolyte films were prepared with two different DES (industrial and from oil-based glycerol) were named D1 and D2, respectively. Fabricated polymer film (D1) with DES (prepared with industrial glycerol) shows excellent physical and thermochemical properties. The molecular and structural characteristics of the film were studied via FTIR and XRD. The surface morphology, thermal and electric properties of film were studied with SEM, TGA, and impedance spectroscopy techniques, respectively. The obtained films were flexible, strong, and transparent. Its properties are ascribed to a strong coherent hydrogen bond network with the matrix of the polymer. Polymer electrolyte film D1 exhibited good ionic conductivity of 1.25×10-3 Scm-1. The prepared polymer film was applied as solid electrolytes in symmetric solid-state supercapacitors. The fabricated EDLC cell exhibits specific capacitance of at voltage with scan rate. Moreover, the prepared electrolyte is biocompatible, environment safe and cost-effective that offers a new path for adaptable electronic devices. Keywords: Green electrolytes, Supercapacitor, Deep eutectic solvent, Hydrogen bond network, Choline chloride-glycerol.