Fe3O4/WO3 Hierarchical Core-Shell Structure: High-Performance and Recyclable Visible-Light Photocatalysis

A facile solvothermal epitaxial growth combined with a mild oxidation route has been developed for the fabrication of a magnetically recyclable Fe3O4/WO3 core-shell visible-light photocatalyst. In this core-shell structured photocatalyst, visible-light-active WO3 nanoplates (the shells) with high surface area are used as a medium to harvest absorbed photons and convert them to photogenerated charges, while conductive Fe3O4 microspheres (the cores) are used as charge collectors to transport the photogenerated charges. This is a new role for magnetite. The Fe3O4/WO3 core-shell structured photocatalysts possess large surface-exposure area, high visible-light-absorption efficiency, stable recyclability, and efficient charge-separation properties, the combination of which has rarely been reported in other visible-light-active photocatalysts. Photoelectrochemical investigations verify that the core-shell structured Fe3O4/WO3 has a more effective photoconversion capability than pure WO3 or Fe3O4. At the same time, the visible-light photocatalytic ability of the Fe3O4/WO3 photocatalyst has significantly enhanced activity in the photodegradation of organic-dye materials. The results presented herein provide new insights into core-shell materials as high-performance visible-light photocatalysts and their potential use in environmental protection.