Preparation of Li2TiO3 by hydrothermal synthesis and its structure evolution under high energy Ar+ irradiation

Ultrafine lithium titanate (Li2TiO3) powder was synthesized by hydrothermal method. The phase formation and transition condition among alpha,beta, and gamma-Li2TiO3 were discussed. XRD and ICP-AES showed the single alpha-phase was formed at 180 degrees C with 2 h hydrothermal reaction, and it transited into beta-phase at 400 degrees C. SEM observation and EDS analysis confirmed the dissolution of TiO2 and the formation of alpha-Li2TiO3 proceeded simultaneously with preferable growth direction of (-133) lattice. During the phase transition, the powder maintained the small crystallite, which facilitated the fabrication of Li2TiO3 bulk with small grain size. After the Ar+ irradiation, the surface region to the depth of 3 mu m of Li2TiO3 ceramic was affected, where the decrease of crystallization and disturbance of short-range order were confirmed by GIXRD and Raman spectroscopy. In spite of the structure change at the surface area, the ceramic bulk maintained the same. (C) 2017 Elsevier Ltd. All rights reserved.