A sandwich-like heterostructure of TiO2 nanosheets with MIL-100(Fe): A platform for efficient visible-light-driven photocatalysis

Abstract Hierarchical heterostructures with specific compositions, morphology and functionalities are important for applications in many fields such as catalysis, energy storage and conversion. Herein, hierarchical sandwich-like heterostructures were prepared by a self-assembly method of growing MIL-100(Fe) on host two dimensional (2D) TiO 2 nanosheets (TiO 2 NS). The introduction of porous MIL-100(Fe) on TiO 2 NS improves the adsorption ability of nanocomposites owing to the porous tunnel adsorbing organic molecules and high surface area. In addition, the interfaces of TiO 2 NS and MIL-100(Fe) provide platforms for rapid photoexcited electrons transfer and enhance the photocatalytic activity of TiO 2 NS@MIL-100(Fe) nanocomposites. The resulting sandwich-like TiO 2 NS@MIL-100(Fe) nanocomposites with enhanced adsorption ability and superior separation of photogenerated electron-hole pairs exhibited improved photoactivity toward degradation of methylene blue dye (MB) under visible light ( λ  ≥ 420 nm). TiO 2 NS@MIL-100(Fe) nanocomposites offer an useful platform to integrate photocatalytic semiconductor and porous MOFs into hierarchical nanostructures with high surface areas and efficient electrons transfer for enhanced photocatalytic performance.