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

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·g_cat⁻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.