Semicrystalline SrTiO 3 -Decorated Anatase TiO 2 Nanopie as Heterostructure for Efficient Photocatalytic Hydrogen Evolution.

The coupling of TiO 2 and SrTiO 3 through elaborate bandgap engineering can provide synergies for highly efficient photocatalysts. To further improve the separation between photogenerated electrons and holes, a nano-heterostructured combination of semicrystalline SrTiO 3 (S-SrTiO 3 ) and anatase TiO 2 nanoparticles is designed, and an optimized interface is achieved between uniformly grown S-SrTiO 3 and metal organic framework (MOF)-derived anatase TiO 2 through a controlled hydrothermal process. Besides tuning of the bandgap and broadening of the absorption spectral range, S-SrTiO 3 particles alleviate charge carrier recombination benefiting from the coupling of the semicrystalline SrTiO 3 around the interface. Additionally, highly dispersed S-SrTiO 3 on TiO 2 provides a good spatial distribution of active sites and the abundant carbon remained from MOF may reduce charge transport resistance. Moreover, the rapid transfer within the nano-heterostructure promotes the separation of the photogenerated charge carriers. With the above predominant architecture, when used as a photocatalyst, the as-synthesized S-SrTiO 3 /TiO 2 heterostructure exhibits exceptionally high photocatalytic performance of 13 005 µmol h -1 g -1 for H 2 production, exceeding most oxide-based photocatalysts reported. This study might provide mechanistic insights into a new perspective for the design and preparation of photocatalysts with novel structure and enhanced catalysis activity.