Fabrication of a magnetic ternary ZnFe(2)O(4)/TiO(2)/RGO Z-scheme system with efficient photocatalytic activity and easy recyclability

A magnetic composite based on TiO(2) nanosheets, ZnFe(2)O(4) and reduced graphene oxide (RGO) was synthesized by a one-step hydrothermal synthesis method, which possessed the band structure of a Z-scheme photocatalytic system. The properties and structures of the samples were characterized by XRD, UV-Vis DRS, Raman spectroscopy, SEM, EDS, XPS and PL spectroscopy. Compared with TiO(2) nanosheets and the TiO(2)/RGO composite, the obtained ternary composite with 3 wt% RGO exhibited a significant enhancement in photocatalytic activities, attributed to the efficient charge separation induced by the fabricated Z-scheme system. About 99.7% of p-nitrophenol (p-NP) degraded within 60 min under simulated solar irradiation. Trapping experiments showed that superoxide anions (˙O(2)(−)) and hydroxyl radicals (˙OH) were the main active species in the p-NP photocatalytic degradation. Finally, a possible photocatalytic mechanism of Z-scheme ZnFe(2)O(4)/TiO(2)/RGO was proposed based on the results of trapping experiments and the energy bands of TiO(2) and ZnFe(2)O(4).