Preparation of lithium niobate particles via reactive molten salt synthesis method

Abstract Lithium niobate (LiNbO3, LN) is one of the key materials for optical based technologies. In this paper, we report an effective, simple, cheap and very fast molten salt method for gram-scale synthesis of single-crystalline LN particles in which a mixture of Nb2O5–LiCl is heat treated at a temperature above the melting point of LiCl for few minutes. The product consisted of LN and other Li–Nb–O phases when the mixture was heated in air. In contrast, single-phase LN was synthesised by heating the mixture in a humid argon flow. In this process, the molten salt acts as both the reaction medium and the Li-source. Synthesised LN was characterised by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, differential scanning calorimetry, and Raman spectroscopy. The mechanism of the process is also discussed.