Microstructure and Ionic Conductivity of Sb-doped Li7La3Zr2O12 Ceramics

The garnet-related oxides Li7-xLa3Zr2-xSbxO12 (x = 0, 0.075) were prepared by solid-state reaction method. Crystal structure, microstructure, conductivity, and element distribution were characterized for the pure and Sb-doped Li7La3Zr2O12. Ionic conductivity of the Li7La3Zr2O12 is enhanced by Sb doping. An amorphous Li-La-Zr-Al-O thin film which is formed on the grain boundary of Sb-doped samples not only suppresses the abnormal grain growth but also eliminates the pores on the grain boundary. The ionic conductivity of Sb doped Li7-xLa3Zr2-xSbxO12 ceramic with x = 0.075 sintered at 1160°C reaches about 3.40×10 S/cm.