Constructing Z-scheme Fe3N/BiVO4 heterojunction via electrostatic self-assembly toward high visible-light photocatalytic hydrogen evolution

Abstract

Fe3N/BiVO4 nanocomposites without noble metals were synthesized by a simple electrostatic self-assembly method. The morphology, crystal structure, composition and properties of the samples were studied by XRD, SEM, TEM, UV–vis and XPS. Under visible light irradiation, the average hydrogen production efficiency of 9 wt% Fe3N/BiVO4 nanocomposites reached 1420.7 μmol h−1 g−1, about 4 times than that of pure BiVO4. After four cycle experiments, the hydrogen production of 9 wt% Fe3N/BiVO4 is basically the same, indicating that the sample has good cycle stability. The enhancement of the activity and stability of the photocatalyst is mainly due to the fact that Fe3N is loaded on the surface of BiVO4, forming a Z-scheme heterojunction, which hinders the recombination of photogenerated electron hole pairs and greatly improves the separation efficiency of charge carriers.