Facile construction of Z-scheme AgCl/Ag-doped-ZIF-8 heterojunction with narrow band gaps for efficient visible-light photocatalysis

It is of great importance to fabricate photocatalyst with high photocatalytic activity, and the formation of Zscheme heterojunction photocatalyst has been proved to be an effective way to restrain the recombination of photo-induced carriers. In this work, Z-scheme AgCl/Ag-doped-ZIF-8 heterojunction is synthesized via a two-step process involving appropriate amount of cationic Ag ion doping into the imidazole ring of ZIF-8 framework and the precipitation of AgCl onto this Ag-doped-ZIF-8. The successful doping of ZIF-8 which decreases the band gap energy, enhances the light harvesting. Besides, the separation efficiency of photo-induced carriers is further improved due to the formation of Z-scheme AgCl/Ag-doped-ZIF-8 heterojunction, which is confirmed by photoelectrochemical experiments. As a result, the as-prepared AgCl/Ag-doped-ZIF-8 photocatalyst possesses excellent photocatalytic activity under visible light illumination. This work will provide a novel perspective for the design and construction of Z-scheme heterojunction for highly efficient photocatalysis.