Copper doped titanium dioxide as a low-cost visible light photocatalyst for water splitting

[Display omitted] •Cu doped TiO2 was synthesized to enhanced the photocatalytic water splitting.•Cu doped TiO2 exhibited excellent visible-light photocatalytic H2 generation (45.6 mmol/h)•Cu-TiO2 can reused five times without the loss of H2 production capacity.•Cu-TiO2-based photocatalyst has potential to apply for sustainable H2 production. Titanium dioxide (TiO2) based materials were used in many fields such as energy application, biological and environment remediation control. In this study, copper-doped TiO2 (Cu-TiO2) was synthesized and investigated for photocatalytic water splitting hydrogen (H2) evolution. The doping of Cu ions not only increased the oxygen vacancies but also improved the charge separation of photocatalyst. The Cu-TiO2 displayed a higher the rate of H2 evolution (45.6 mmol/h) as compared to undoped TiO2 (0.73 mmol/h). The reused of material was identified and the photocatalytic water splitting mechanism of Cu-TiO2 was proposed. The results showed that, Cu-TiO2 had high stability after reusing for 5 consecutive cycles without the loss of H2 production capacity. In addition, practical application and future research were discussed in details. This work may contribute to the potential application of TiO2-based photocatalyst for water splitting in order to produce H2 gas as green energy.