Influence of Sintering Temperature on Performance of Aluminum Oxide Solid Electrolytes

Al₂O₃ solid electrolytes were synthesized via solid state reaction. The formation of β^″/β phase, density and ionic conductivity of Al₂O₃ at various sintering temperatures were investigated by Xray diffractionscanning electron microscopy and electrochemical impedance spectroscopy, respectively. The results show that the performance of alumina electrolytes is related to the sintering temperature, and the optimum sintering temperature is 1600.The β^″ phase content, density and ionic conductivity firstly increases and then decreases with increasing the sintering temperature. The ionic conductivity depends on the phase structure and the compactness of the material. During the process of the temperature elevated, the conductive process is controlled by the grain boundary into a grain control. The temperature range controlled by the grain boundary decreases as the sintering temperature increases.