Structure and ionic conductivity of cubic Li7La3Zr2O12 solid electrolyte prepared by chemical co-precipitation method

•Cubic Li7La3Zr2O12 electrolyte was synthesized by Chemical co-precipitation method.•Tetragonal LLZO transformed into cubic LLZO when the temperature was above 1150 °C.•The particle size of LLZO precursor powder was in the range of 0.5 ~ 1 μm.•The total ionic conductivity of sample sintered at 1180 °C was 2.0 × 10− 4 S cm− 1 at 30 °C.•The activation energy was 0.25 eV.

Solid electrolyte Li7La3Zr2O12 (LLZO) powder was successfully synthesized by co-precipitation method. The LLZO powder calcined at 850 °C with a tetragonal phase was confirmed by X-ray diffraction (XRD). Scanning electron microscopy (SEM) showed that the particles sizes of LLZO precursor powder were in the range of 0.5 ~ 1 μm. LLZO pellets were sintered at different temperatures from 1150 to 1200 °C in air atmosphere. When the temperature was above 1150 °C, tetragonal LLZO would completely transform into cubic phase. The total ionic conductivity of LLZO pellet sintered at 1180 °C was 2.0 × 10− 4 S cm− 1 at 30 °C, and the activation energy was 0.25 eV. This result indicates that high quality LLZO solid electrolytes can be obtained by chemical co-precipitation method.