Effect of partial substitution of Ta2O5 by ZrO2 on the structure and ionic conductivity of Li2O-Ta2O5-2SiO2 glass and glass-ceramics

LiTaSiO5 system is considered as type of solid electrolyte with great potential for application as ionic conductor. It is well-known that it is difficult to obtain pure dense LiTaSiO5 phase by traditional synthesis methods, because dielectric LiTaO3 phase easily precipitates during synthesis, which affects ionic conductivity. In this work, a glass -ceramic electrolyte with main LiTaSiO5 phase was obtained by controlled crystallization of Li2O-Ta2O5-2SiO(2) glass without porosity. The precipitation of LiTaO3 phase at the grain boundary was effectively inhibited by adding an appropriate amount of ZrO2. Among all the glass -ceramic samples, the glass containing 4.76 mol% ZrO2 had the maximum ionic conductivity of 8.40 x 10(-6) S/cm at 25 degree celsius, which is two order of magnitude greater than the ionic conductivity of the matrix glass. These glassceramic samples have the potential to be used as solid electrolytes in electrochemical applications.