Micro-/nanostructured ZnFe 2 O 4 hollow sphere/GO composite for structurally enhanced photocatalysis performance

The pollution of organic dyes has become a serious environmental problem. It is still urgent to prepare a highly efficient and environment-friendly photocatalyst for pollutants removal. Herein, a micro-/nanostructured ZnFe 2 O 4 hollow sphere/GO (ZnFe 2 O 4 /GO) composite photocatalyst was prepared through a one-step hydrothermal method with high performance and recycling property. The obtained micro-/nanostructured composite was assembled by ZnFe 2 O 4 hollow spheres and GO nanosheets. The special self-assembled hollow nanosphere structure enlarged visible light harvesting. In addition, luminescence property demonstrates that the introduction of graphene oxide (GO) inhibits the recombination of electron–hole pairs, leading to enhancement of photocatalytic activity of ZnFe 2 O 4 . Under visible light irradiation, the ZnFe 2 O 4 /GO composite exhibited excellent photocatalytic activity for Congo red (93%), higher than that of the pure ZnFe 2 O 4 hollow spheres (only 60%) and commercial ZnFe 2 O 4 nanoparticles (40%). Moreover, the micro-/nanostructured ZnFe 2 O 4 /GO composite photocatalyst can be regenerated with high efficiency and remains over 80% activity after seven regenerations. This work not only supplies a new strategy for one-step preparation of such ZnFe 2 O 4 /GO micro-/nanostructures for structurally enhanced photocatalysis, but also provides a highly efficient photocatalyst for wastewater treatment. Graphical abstract