Recent advances in hollow metal-organic frameworks and their composites for heterogeneous thermal catalysis

Hollow metal-organic frameworks (HoMOFs) as emerging materials have been arousing great interest in heterogeneous catalysis with respect to the solid counterparts, mainly because of their unique and intriguing features such as high surface to volume ratio, large void space, short channel length, and more exposed active sites. To achieve diverse catalysis, it is of great importance to combine HoMOFs with other active components for constructing smart composites. In this review, the recent advances in HoMOFs and their composites for heterogeneous catalysis are summarized. Firstly, the synthetic strategies for various HoMOFs with single shell, double shells or multiple shells are summarized, while their composites with yolk-shell, hollow sandwich and hollow satellite structures are described. Secondly, various catalytic reactions over HoMOFs and their composites are discussed, and moreover, the relationships among the active components, structures and their performances are illustrated. Thirdly, the potential challenges and future development on HoMOFs based nanocatalysts are proposed. This review will bring some insights for better design and fabrication of heterogeneous nanocatalysts with the well-defined hollow structures.