Fabricating Fe3O4-schwertmannite as a Z-scheme photocatalyst with excellent photocatalysis-Fenton reaction and recyclability

Here we reported an effective method to solve the rate-limiting steps, such as the reduction of Fe3+ to Fe2+ and an invalid decomposition of H2O2 in a conventional Fenton-like reaction. A magnetic heterogeneous photocatalyst, Fe3O4-schwertmannite (Fe3O4-sch) was successfully developed by adding Fe3O4 in the formation process of schwertmannite. Fe3O4-sch shows excellent electrons transfer ability and high utilization efficiency of H2O2 (98.5%). The catalytic activity of Fe3O4-sch was studied through the degradation of phenol in the heterogeneous photo-Fenton process. Phenol degradation at a wide pH (3 - 9) was up to 98% within 6 min under visible light illumination with the Fe3O4-sch as heterogeneous Fenton catalyst, which was higher than that using pure schwertmannite or Fe3O4. The excellent photocatalytic performance of Fe3O4-sch is ascribed to the effective recycling between Fe3+ and Fe2+ by the photo-generated electron, and also profit from the formation of the “Z-Scheme” system. According to the relevant data, photocatalytic mechanism of Fe3O4-sch for degrading phenol was proposed. This study not only provides an efficient way of enhancing heterogeneous Fenton reaction, but also gives potential application for iron oxyhydroxysulfate mineral. [Display omitted]