Hydrothermal Synthesis of Brookite

Abstract

Abstract Hydrothermal synthesis of brookite was performed at 110-200 °C within 24 h using amorphous TiO2 and sodium salts as the starting material. Brookite was obtained as an almost single phase at 200 °C and TiO2 / NaOH mole ratio ≅ 1. By the results of XPS and UV-vis measurements, brookite was considered to be formed from sodium titanate by releasing Na+ and H+ of the surface accompanied by oxidation of Ti in the structure.