Holey defected TiO2 nanosheets with oxygen vacancies for efficient photocatalytic hydrogen production from water splitting

Introduction of surface oxygen vacancies is an efficient strategy to enhance the photocatalytic activity of metal oxides by inhibiting the recombination of photogenerated hole and electrons. However, owing to limited exposed surface, maximizing the concentration of oxygen vacancies is still challenging. Herein, utilizing a sacrificial template strategy, unique 2D holey defective TiO 2 nanosheets (HD-TiO 2 NSs) with abundant oxygen vacancies are synthesized for water splitting. This HD-TiO 2 NSs consisting of a large number of interconnected TiO 2 nanopartices possess a large number of mesopores , rendering the facile generation of abundant oxygen vacancies. The resulting HD-TiO 2 NSs photocatalyst exhibited excellent hydrogen production activity with rate of 8.99 mmol•g –1 •h –1 under solar light irradiation, which is 2.83 and 26.8 times higher than those of H-TiO 2 NSs catalyst and defected TiO 2 bulk counterpart, respectively, and ranks in the highest photocatalytic activities of the reported defective TiO 2 photocatalysts. This work demonstrates an efficient strategy to enhance the photocatalytic activity by engineering defect and special 2D holey nanostructure .