Effect of Si, In and Ge doping on high ionic conductivity of Li7La3Zr2O12

The doping effect of Si, In and Ge in Li7La3Zr2O12 as the solid electrolyte was studied via conventional solid-state reaction. The crystal structure, cross-sectional morphology, element distribution and conductivity were characterized for the undoped and doped LLZ ceramics. Our results showed that Si and In doping deteriorate electrical properties of LLZ as electrolyte, while Ge doping obviously improves properties. Ge might thus be a promising element for further increasing the ionic conductivity of LLZ ceramics. (C) 2012 Elsevier B.V. All rights reserved.