Datensatz

Zusammenfassung

Hydrogen reduction of TiO₂ to generate surface Ti³⁺ can significantly increase the photochemical activity under solar-light illumination. However, the low surface areas of commercial TiO₂ limit their photocatalytic activities. Herein, we report a high surface area ordered mesoporous black TiO₂, which exhibits an improved photocatalytic performance. The TiO₂ material was prepared by using a highly ordered mesoporous carbon CMK-3 as a hard template, which possesses very high surface area, large pore volume and uniform mesopores. By using the advantage of pore confinement in the mesoporous carbon template, TiO₂-carbon composites were annealed at different temperatures to investigate the influence of the crystallinity of TiO₂ on the photocatalytic hydrogen production. TiO₂ calcined at 500 °C, having a high surface area (up to 158 m² g⁻¹), large pore volume (up to 0.62 cm³ g⁻¹), uniform pore size (5–6 nm), and anatase crystal structure, indicated the highest hydrogen generation rate. Since the TiO₂ has been treated at a higher temperature in the confinement of the mesoporous carbon, the TiO₂ can easily be reduced at 500 °C under hydrogen atmosphere to generate surface Ti³⁺ species without destruction of the mesostructure and exhibits a high solar-driven hydrogen evolution rate (188 μmol h⁻¹), which is more than two times higher than that of commercial TiO₂ (82 μmol h⁻¹).