A novel synthetic route of garnet-type Li6.5La3Zr1.5Ta0.5O12 using pyrochlore-type La2Zr2O7 and weberite-type La3TaO7 as starting materials

Abstract

We successfully synthesized a garnet-type Li6.5La3Zr1.5Ta0.5O12 polycrystalline sample at a relatively low temperature of 700°C using pyrochlore-type La2Zr2O7 and weberite-type La3TaO7 as precursor oxides. The cubic garnet-type structure with the lattice parameter of a = 1.29577(1) nm was confirmed using powder X-ray diffraction data. The primary particle size of the present Li6.5La3Zr1.5Ta0.5O12 sample was about 2 ¯m, which is considerably smaller than that prepared using conventional solid-state reaction at higher temperatures. Thermogravimetry differential thermal analysis data confirmed that the reaction between LiOH·H2O and precursor oxides occurred above 500°C after the dehydration reaction of LiOH·H2O.