Construction of novel 3D ZnO hierarchical structure with Fe3O4 assist and its enhanced visible light photocatalytic performance

Abstract In order to improve the visible light photocatalytic ability of ZnO semiconductor, a novel 3D Fe3O4/ZnO hierarchical structure (defined as 3D F-ZnO) has been successfully constructed by a Fe3O4 nanosphere assisted hydrothermal method. The forming mechanism was proposed. Its morphology, crystal structure, and visible light response property were studied via SEM, XRD, and DRS. The diameter of 3D F-ZnO was about ˜4.5 µm and it was assembled by numerous of asymmetric cone-shaped ZnO nanorods on a Fe3O4 nanosphere. 3D F-ZnO structure exhibit good optical response property and enhanced visible light photodegradation ability toward Cong red (84%). 3D F-ZnO also displays good ability on the degradation of tetracycline (90%) and methylene blue (60%) under visible light irradiation. Influence of heavy ions, acid groups, water sources on degradation CR was investigated, whose results further confirm that 3D F-ZnO possesses good adaptability in practical application. The 3D F-ZnO can be reused by the magnet and exhibit excellent stability. At last, the enhanced visible light photodegradation ability was explained via its unique morphology, PL and EIS. A synergetic effect mechanism between unique morphology and Fe3O4 was proposed. The primary reactive species of ·OH, ·O2–, and h+ were also confirmed in the photodegradation process. All results suggest that this novel 3D F-ZnO hierarchical structure may have great potential in water treatment and other photocatalytic fields.