▎ 摘　　要

A novel three-dimensional nest-like LiFe5O8/reduced graphene oxide (LiFe5O8/RGO) composite was prepared successfully via a one-pot hydrothermal method. The morphology and properties of the prepared composites were characterized by SEM, XRD, Raman spectroscopy, XPS, VSM, BET and UV-Vis DRS measurements. When compared with rod-like LiFe5O8, nest-like LiFe5O8 and rod-like LiFe5O8/RGO, the nest-like LiFe5O8/RGO composite displayed superior photocatalytic activity for the decomposition of dye under visible light irradiation. The first-order kinetic constant of photodegradation with nest-like LiFe5O8/RGO (0.03004 min(-1)) was approximately 2.21, 4.52 and 6.04 times higher than that of rod-like LiFe5O8/RGO (0.01362 min(-1)), nest-like LiFe5O8 (0.00665 min(-1)) and rod-like LiFe5O8 (0.00497 min(-1)). The improved photocatalytic activity was attributed to the higher visible-light harvesting capacity resulting from the multiple reflections of light, relatively high specific surface area, hierarchical porous structure and effective migration of photo-generated electrons. Based on free radicals trapping experiments, the superoxide radical played a major rote during photocatalytic degradation. According to the estimated band structure and photo-electrochemical measurements, a possible mechanism for the photocatalytic degradation process was discussed in detail. Benefiting from its magnetic properties, the nest-like LiFe5O8/RGO can be easily separated and recycled, exhibiting outstanding stability.