Solvothermal synthesis and visible light absorption of anatase TiO2

• The TiO2 with enriched (001) facet was synthesized by TiB2 powders.
• H2 were produced during the hydrolyzed of TiB2 in the HF solution.
• H2 reduces the Ti4+ of TiO2 in situ and generates the oxygen vacancies.
• The oxygen vacancies in TiO2 increased with the hydrothermal temperature raised.
• The new absorption in the visible region is due to the existence of oxygen vacancy.

Oxygen-deficient anatase TiO2 sheets with dominant (001) facets are becoming a hot research topic due to their promising high activity in heterogeneous reactions. In this work, a series of (001) facets dominated TiO2 with distributed oxygen vacancies and Ti3+ was prepared by a simple hydrothermal method with the TiB2 as a precursor. The as-prepared powders were characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), Transmission Electron Microscope (TEM), X-ray photoelectron spectroscopy (XPS) and UV–visible diffuse reflectance spectroscopy (UV–vis). The results show that the particle size of as-prepared TiO2 increases and its band gap narrows with the hydrothermal temperature increasing from 140 °C to 180 °C. Besides, oxygen vacancies and Ti3+ are generated during the TiB2 hydrolysis, which leads to new absorption spectrum in the visible light region. Photocatalytic test shows that sample prepared at 180 °C presents the highest degradation efficiency.