An intensive study on the AC impedance mechanism of (AgPO_3)_(1-x)(Ag_2SO_4)_x ionic glass systems under various conditions

摘要

Purpose - The purpose of this study is to investigate the effect of the considerable Ag_2SO_4 content on the electrical and dielectric properties of (AgPO_3)_(1-x)(Ag_2SO_4)_x ion glass system as well as to extract thermodynamic parameters. Design/methodology/approach - Glass samples of (AgPO_3)-(1-x)(Ag_2SO_4)_x with different mole ratios of Ag_2SO_4 [x = 0.00, 0.10,0.15,0.20 and 0.25] have been synthesized and used. X-ray diffraction and differential thermal analysis were used to investigate structural and thermal properties, and then the electrical characterizations of the bulk glasses were performed in different frequency and temperature range. Findings - For different ratios of Ag_2SO_4 on AgPO_3, the bulk conductivity is enhanced with increasing the amount of Ag_2SO_4 until the composition of x = 0.20, after which the conductivity decreases. The general behavior of both ε and ε" decreases with increasing frequency and increases with increasing temperature. Complex impedance analysis studied by Z'-Z' and Cole-Cole plot at different temperatures revealed that bulk resistance decreases with temperature. Originality/value - The calculated values of activation free energy, enthalpy and entropy change for different compositions of (AgPO_3)_(1-x)(Ag_2SO_4)_x showed an increase in activation energy and enthalpy when Ag_2SO_4 ratio is increased in (AgPO_3)_(1-x)(Ag_2SO_4)_x composition up to 20%, and then there is a decrease in their values at x = 25%, which may be explained based on non-bridging oxygen.