Environmentally friendly flux growth of high-quality, idiomorphic Li ₅La₃Nb₂O₁₂ crystals

High-quality, idiomorphic, single-phase Li₅La₃Nb ₂O₁₂ crystals were successfully grown using a LiOH flux cooling method at the relatively low temperature of 500 C at a solute concentration of 5 mol %. The grown Li₅La₃Nb ₂O₁₂ crystals had polyhedral shapes with well-developed, flat {211} and {110} faces. Their shapes were relatively uniform, and the average crystal size was approximately 59.2 μm. No aggregation was observed in scanning electron microscopy images. The high crystallinity of the Li ₅La₃Nb₂O₁₂ crystals was confirmed by transmission electron microscopy images. Their lattice parameter was determined from the X-ray diffraction pattern to be a = 1.281 nm, which is consistent with the literature value (a = 1.282 nm). Furthermore, the crystal phase, form, size, and crystallinity of the flux-grown Li₅La₃Nb ₂O₁₂ crystals were obviously dependent on the growth conditions including the solute concentration and holding temperature.