Designed 2D/2D/2D Bi2WO6/Ti3C2/SnNb2O6 Z-scheme heterojunction via interfacial chemical bond with enhanced photocatalytic activity

2D/2D/2D materials are widely used in photocatalysis owing to the advantages of high specific surface area, large contact interface, numerous charge transfer channels and ultrashort charge transfer distance. In this work, 2D/2D/2D Bi2WO6/Ti3C2/SnNb2O6 catalysts were successfully constructed via an anaerobic hydrothermal method. Due to ultrathin 2D Ti3C2 MXene served as an electron mediator and combined with 2D SnNb(2)O6 and 2D Bi2WO6 by Ti-O-Sn interface bond or Ti-O-Bi interface bond to form Z-scheme heterojunction, which could afford charge transfer channels and increase reactive sites. As a result, the Bi2WO6/ Ti3C2/SnNb2O6 composites significantly improved the photodegradation efficiency of tetracycline hydrochloride due to the high redox ability, and its degradation rate in 90 min was 10.22 times that of SnNb2O6. This work provides an effective method to construct 2D/2D/2D Z-scheme heterojunction by tight chemical bond.