Designed Construction of SrTiO3/SrSO4/Pt Heterojunctions with Boosted Photocatalytic H2 Evolution Activity

Graphical A novel photocatalyst is designed with consideration of heterojunction band matching and porous structure. The SrTiO 3 /SrSO 4 heterojunction using Pt as the co-catalyst reaches 396.82 μmol g −1 h −1 , which is 16 times higher than that of SrTiO 3 /Pt. It is proposed that the presence of SrSO 4 provides extra channels for electron transportation as well as promoting photocatalytic activity. Efficient separation of photogenerated electron–hole pairs is a crucial factor for high-performance photocatalysts. Effective electron–hole separation and migration could be achieved by heterojunctions with suitable band structures. Herein, a porous SrTiO 3 /SrSO 4 heterojunction is prepared by a sol-gel method at room temperature followed by an annealing process. XRD characterization suggests high crystallinity of the heterostructure. A well-defined interface between the two phases is confirmed by high-resolution (HR)TEM. The photocatalytic H 2 evolution productivity of the SrTiO 3 /SrSO 4 heterojunction with Pt as co-catalyst reaches 396.82 μmol g −1 h −1 , which is 16 times higher than that of SrTiO 3 /Pt. The boosted photocatalytic activity of SrTiO 3 /SrSO 4 /Pt can be ascribed to the presence of SrSO 4 , which promotes the transfer and migration of photogenerated carriers by forming the heterojunction and porous structure, which provides a large amount of active sites. This novel porous heterostructure brings new ideas for the development of high-efficiency photocatalysts for H 2 release.