Research progress in the design, fabrication and application of Z-scheme heterojunction photocatalysts

Traditional heterojunction boasts such advantages as enlargement in optical response range and facilitation in carrier separation. However, its redox ability is insufficient. Z-scheme heterojunction is put forward based on artificial photosynthesis, a simulation of plant photosynthesis in nature. With respect to the single photocatalyst and traditional heterojunction, Z-scheme heterojunction has distinct advantages, e.g. the effective separation of electron-hole pairs, reduced recombination of photo-induced carrier, strong redox active site, expanded light response range, high photocatalytic activity, etc. In this paper, the reaction mechanism, construction method and application of liquid phase Z-scheme heterojunction, all-solid-state Z-scheme heterojunction and direct Z-scheme heterojunction are reviewed. Finally, the characteristics of several types of Z-scheme heterojunction were briefly summarized and compared, and the challenges and prospects for the development of Z-scheme photocatalytic systems are proposed.