Dielectric properties and electrical conductivity of Ternary Zinc Magnesium Phosphate Glass-derived hydrogel

Abstract

Leakage problem and contact resistance are the major problems for liquid electrolyte and solid-state electrolyte, respectively. In this research, a highly viscous ternary phosphate glass-derived hydrogel was proposed as high proton-conducting electrolyte that may overcome the problems and applicable to power storage devices. Before hydration, a series of ternary zinc magnesium phosphate glasses having the composition (ZnO)30.(MgO)x.(P2O5)70-x with x = 5, 8, 10, 13, 15, 18, and 20 mole % were prepared by melt quenching technique. All the samples were confirmed in amorphous phase by X-ray diffraction (XRD) analysis. Glass powder from each glass samples were successfully transformed into hydrogel product via hydration after reaction with distilled water (DW) with ratio mixture 1:0.5 and 1:1. Density, molar volume and Fourier Transform Infrared (FTIR) spectroscopic measurement have been used to characterize the physical properties of solid glass and glass-derived hydrogel. Result of both density and molar volume was correlated with network polymerization. IR spectra of solid glass and hydrogel were measured in the wavenumber range of 650 cm-1 to 4000 cm-1 at ambient temperature. It was found that the absorption band of phosphorusoxygen- metal (P-O-M) bonding which present in glass powder structure disappeared in the hydrogel structure due to hydration process. However, the divalent cations may attach to phosphate chain by chelation. The dielectric properties of the hydrogel samples were characterized by impedance analyzer in frequency range of 4 Hz to 1 MHz. It was revealed that CZ05 (1:1) hydrogel sample has highest dielectric constant, dielectric loss and electrical conductivity values among studied samples.