Construction of SrTiO3-LaCrO3 Solid Solutions with Consecutive Band Structures for Photocatalytic H2 Evolution under Visible Light Irradiation

SrTiO3-LaCrO3 continuous solid solutions with LaCrO3 content ranging from 0.00 to 1.00 were prepared via a polymerized complex method. The light absorption ability of SrTiO3 was improved by the consecutive tuning of the bandgap upon the introduction of LaCrO3 (up to 570 nm). The solid solutions exhibited significantly enhanced photocatalytic activities for H-2 evolution under visible light irradiation, with an optimized H-2 evolution rate of 1368 mu mol h(-1) g(-1) obtained when LaCrO3 content was 0.10 (with 1 wt% Pt as cocatalyst), corresponding to an apparent quantum yield of 3.68% at 400 nm. Supported by comprehensive characterization, the improved photocatalytic performance was attributed to the simultaneously adjusted conduction band and valance band originating from the hybridization of Cr 3d, Ti 3d and O 2p orbitals, as well as the accelerated separation and migration of photogenerated charge carriers derived from the distortion of TiO6 octahedra.

Automated summary

In this study, SrTiO3-LaCrO3 continuous solid solutions were prepared using a polymerized complex method. The introduction of LaCrO3 effectively adjusted the bandgap of SrTiO3, leading to improved light absorption ability and significantly enhanced photocatalytic activities. The optimized H-2 evolution rate reached 1368 mu mol h(-1) g(-1) with 0.10 LaCrO3 content, and the improved photocatalytic performance was attributed to the hybridization of Cr 3d, Ti 3d, and O 2p orbitals, as well as the distortion of TiO6 octahedra.