Boosted photodegradation of tetracycline hydrochloride over Z-scheme MIL-88B(Fe)/Bi2WO6 composites under visible light

Metal-organic frameworks (MOFs) have attracted great interest in the field of photocatalysis because of their adjustable porous structure and semiconductor properties. In this research, a new type of MIL-88B(Fe)/Bi2WO6 was successfully prepared by growing MIL-88B(Fe) on the surface of flower-like Bi2WO6 spheres. The structures of materials were characterized through XRD, BET, XPS, SEM, TEM, EDX and FT-IR. 7-MIL-88B(Fe)/Bi2WO6 exhibits the highest photocatalytic performance with a degradation rate of 96.4% within 90 min under visible light irradiation. Compared with pure Bi2WO6 or MIL-88B(Fe), 7-MIL-88B(Fe)/Bi2WO6 exhibits the largest specific surface area to provide more active sites. Additionally, the ·O2- and ·OH played dominant roles during the photocatalytic degradation process based on trapping and ESR tests. Through cyclic experiments, MIL-88B(Fe)/Bi2WO6 composites show good stability and degradation efficiency, indicating its application potential in the environmental field.