Impact of Postprocessing Approaches and Interface Cocatalysts Regulation on Photocatalytic Hydrogen Evolution of Protonic Titanate Derived TiO2 Nanostructures

Abstract

TiO2–based photocatalysis system for splitting water into hydrogen offers a sustainable and green technology to produce clean hydrogen energy. However, pristine TiO2 still exists inherent shortcomings restricting its practical applications. Herein, the impact of postprocessing approaches of protonic titanate on engineering of oxygen vacancy and photocatalytic hydrogen evolution of TiO2−x is studied. Subsequently, interfacial cocatalysts are successfully involved in the optimized TiO2−x for enhanced photocatalytic hydrogen evolution. TiO2−x with the highest photocatalytic hydrogen evolution performance of 3112.09 μmol g−1 h−1, denoted as TiO2–C, is selected to adjust the interface with Cu and MoS2 respectively. Cu–TiO2–C and MoS2–TiO2–C composites are synthesized to enhance the separation ability of photogenerated electron‐hole pairs and significantly improve the photocatalytic hydrogen evolution performance. The photocatalytic hydrogen evolution rates of 5 wt% Cu–TiO2–C and 40 wt% MoS2–TiO2–C are 9225.75 and 5765.48 μmol g−1 h−1, respectively. It is proved that different postprocessing methods can tune the content of oxygen vacancy in TiO2−x and regulate the photocatalytic hydrogen evolution performance of TiO2−x materials. The interface regulation of the cocatalyst also contributes to the separation of photogenerated electron‐hole pairs and serves as active sites to enhance hydrogen evolution performance.

Keywords

• cocatalysts
• hydrogen evolution
• oxygen vacancies
• protonic titanate
• TiO2