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

摘要

We successfully synthesized a garnet-type Lisub6.5/subLasub3/subZrsub1.5/subTasub0.5/subOsub12/sub polycrystalline sample at a relatively low temperature of 700°C using pyrochlore-type Lasub2/subZrsub2/subOsub7/sub and weberite-type Lasub3/subTaOsub7/sub 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 Lisub6.5/subLasub3/subZrsub1.5/subTasub0.5/subOsub12/sub sample was about 2 μm, 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·Hsub2/subO and precursor oxides occurred above 500°C after the dehydration reaction of LiOH·Hsub2/subO.