Novel 2d Snnb2o6/Ag3vo4 S-Scheme Heterojunction With Enhanced Visible-Light Photocatalytic Activity

At present, photocatalytic technology for degradation of organic matter is a promising water treatment technology. Two-dimensional (2D) nanomaterials are getting more and more attention based on unique physical and chemical properties. In this work, 2D SnNb2O6 nanosheets were prepared by hydrothermal method, and then Ag3VO4 was loaded on the surface of SnNb2O6 nanosheets by chemical deposition to form a compact and stable step-scheme (S-scheme) heterostructure. S-scheme system not only efficiently separated the charge carriers spatially, but also retained the electrons with higher reduction ability and holes with higher oxidation ability. Therefore, the novel SnNb2O6/Ag3VO4 S-scheme heterojunction shows the best photocatalytic activity, which is much better than pristine SnNb2O6 and Ag3VO4. The constant K-app of SnNb2O6/Ag3VO4 heterojunction is calculated to be 0.2256 min(-1), which is 16.2 and 1.6 folds higher than that of the pristine SnNb2O6 (0.0139 min(-1)) and Ag3VO4 (0.1395 min(-1)), respectively. Moreover, the SnNb2O6/Ag3VO4 heterojunction maintains good photostability in 3 cycles.