H-doped TiO_2-x prepared with MgH₂ for highly efficient solar-driven hydrogen production

Efficient utilization of visible light with high stability remains a critical challenge for solar-driven photochemical generation of hydrogen (H₂) using particulate photocatalysts. Black TiO₂ was introduced with remarkable enhancement of visible light absorption, but its efficiency in the visible light has not reached the desired level for real-world applications. Here we report a gold-colored H-doped TiO_2-x (H:TiO_2-x) nanoparticles prepared by controlled reduction via simultaneous presence of [Mg] and [H], which are obtained from the decomposition of MgH₂. The H-doped TiO_2-x exhibits a significant activity (16.1 mmolg⁻¹h⁻¹) and remarkable stability after Pt deposition for solar-driven H₂ generation from methanol-water. The excellent photoactivity of H-doped TiO₂ can be attributed to oxygen vacancies and H doping at the reduced TiO_2-x surface generated by [Mg] and [H]. The H-doped TiO₂ is also producing H₂ from methanol-seawater with a rate of 6.1 mmolg⁻¹h⁻¹ under simulated sunlight.