Hierarchical LaTiO2N/Sn3O4 heterojunction with intimate interface contact for enhanced photocatalytic water splitting

Abstract

LaTiO2N/Sn3O4 heterojunction with type-II band structure and hierarchical microstructure was constructed by decorating Sn3O4 nanoflowers and nanoflakes intimately on the surface of LaTiO2N nanosheets via a facile hydrothermal method. Compared with pure Sn3O4 and bare LaTiO2N, the photocatalytic H2 evolution activity for LaTiO2N/Sn3O4 heterostructure was boosted by ∼3 and ∼52 times, respectively, reaching 887 μmol·h−1·gcat−1. The mechanism for the elevated photocatalytic performance was systematically disclosed on the basis of comprehensive characterizations. Specifically, the introduced LaTiO2N extended the visible light absorption range to ∼600 nm, endowing Sn3O4 with more photogenerated charge carriers. Subsequently, the type-II band structure expedited the separation and migration of charge carriers, diminishing the internal recombination, thereby enhancing the photocatalytic activity. This work affords a new avenue for designing tin oxide-based and oxynitrides-based heterojunction.