Band gap engineering of metal-organic frameworks for solar fuel productions

By exploiting the merits of both inorganic and organic photocatalysts, metal-organic frameworks (MOFs) provide a powerful way and bright prospect for developing novel materials for solar fuel productions due to the diverse choices of organic linkers and metal nodes as well as their flexible coordination modes. An in-depth and comprehensive understanding of the intrinsic correlation between the structures and band gaps of MOF-based semiconductors will provide a guide for constructing visible-light response MOFs for solar fuel productions. In this review, we systematically summarize the researches of band gap engineering of MOFs according to the category of linkers, nodes and guests. The various strategies for tuning the band gaps are discussed in detail, and then the latest relevant studies on photocatalytic H2O and CO2 reduction reactions are simply exemplified. Finally, the challenges and perspectives using MOFs for photocatalytic H2O and CO2 reduction reactions are discussed. It is expected that this review will provide a deep understanding to the development of new visible-light responsive MOF-based photocatalysts and their applications in solar fuel productions.