In-situ construction of ternary Ti3C2 MXene@TiO2/ZnIn2S4 composites for highly efficient photocatalytic hydrogen evolution.

Facing the demand of cleaning energy, the development of efficient photocatalysts for hydrogen evolution is a promising way to realize solar-to-chemical energy conversion for solving energy crisis. Hence, a novel hierarchical Ti 3 C 2 MXene@TiO 2 /ZnIn 2 S 4 photocatalyst with rapid charge transfer channels was constructed by two-step hydrothermal for efficient hydrogen production, adopting hydrothermal oxidation to in-situ synthesize Ti 3 C 2 MXene embedded with TiO 2 nanosheets (M@TiO 2), which was applied to load ZnIn 2 S 4 (ZIS). The hybridized photocatalyst with optimized ZIS amount had a hydrogen generation rate of 1185.8 μmol/g/h, which was higher than that of M@TiO 2 and pure ZIS. That was originated from the outstanding light harvesting of ZIS and Ti 3 C 2 , sufficient active sites of Ti 3 C 2 , intimate interfacial contact, and efficient separation and transfer of photogenerated charges via heterojunction. The favorable and rapid charge transfer routes included type-II heterojunction between ZIS and TiO 2 nanosheets, Schottky junction of Ti 3 C 2 /semiconductor, and metallic Ti 3 C 2 with high conductivity. This work revealed the Schottky junction forming between ZIS and Ti 3 C 2 , and hierarchical M@TiO 2 could be served as advantageous platform and efficient cocatalyst to construct MXene-based photocatalyst. [ABSTRACT FROM AUTHOR]