Constructing SrTiO₃ -TiO₂ Heterogeneous Hollow Multi-shelled Structures for Enhanced Solar Water Splitting

Constructing hollow multi-shelled structures (HoMSs) has a significant effect on promoting light absorption property of catalysts and enhancing their performance in solar energy conversion applications. A facile hydrothermal method is used to design the SrTiO₃ -TiO₂ heterogeneous HoMSs by hydrothermal crystallization of SrTiO₃ on the surface of the TiO₂ HoMSs, which will realize a full coverage of SrTiO₃ on the TiO₂ surface and construct the SrTiO₃ /TiO₂ junctions. The broccoli-like SrTiO₃ -TiO₂ heterogeneous HoMSs exhibited a fourfold higher overall water splitting performance of 10.6 μmol h^-1 for H₂ production and 5.1 μmol h^-1 for O₂ evolution than that of SrTiO₃ nanoparticles and the apparent quantum efficiency (AQE) of 8.6 % at 365 nm, which can be mainly attributed to 1) HoMS increased the light absorption ability of the constructed photocatalysts and 2) the SrTiO₃ -TiO₂ junctions boosted the separation efficiency of the photogenerated charge carriers.