Immobilization of Metal–Organic Framework MIL-100(Fe) on the Surface of BiVO4: A New Platform for Enhanced Visible-Light-Driven Water Oxidation

The development of new dual functional photocatalysts is highly desirable for conversion and storage of solar energy. Herein, we first constructed hierarchical structure MIL-100(Fe)@BiVO₄ in situ growing MIL-100(Fe) nanoparticles (NPs) on the surface of decahedron BiVO₄ under mild hydrothermal conditions. The as-synthesized hybrid nanostructure is unambiguously determined using a series of characterization methods. These results demonstrate that the ultra-tiny MOF MIL-100(Fe) particles are immobilized on the surface of decahedron BiVO₄ and the composite exhibits a strong interaction between BiVO₄ and MIL-100(Fe). This hybrid material MIL-100(Fe)@BiVO₄ is employed as a photocatalyst for water oxidation reaction and demonstrates higher O₂ production activity in comparison with bare BiVO₄. The best performance obtained at the optimal mass percentage of MIL-100(Fe) (8.0 wt %) reaches 333.3 μmol h^-1 g^-1 of the O₂ evolution rate irradiated with visible light, which is almost 4.3 times higher than bare BiVO₄ (77.3 μmol h^-1 g^-1). The enhanced water oxidation performance is due to the more efficient interfacial electron-hole transfer between MIL-100(Fe) and BiVO₄, which is verified by the results of various photo-electrochemical characterizations. Moreover, the as-prepared composite MIL-100(Fe)@BiVO₄ also displays excellent stability for visible-light-driven water oxidation. This study affords a rational strategy for the controllable construction by loading metal-organic frameworks on a semiconductor surface, which is a good reference for other artificial photosystems.