MIL-101(Fe)/WS 2 composites activated Na 2 S 2 O 8 with visible light for removal of tetracycline.

MIL-101(Fe)/WS 2 catalyst was composited using a solvothermal method. To study the physical and chemical properties of the composite material, a series of characterizations such as scanning electron microscope (SEM), X-ray diffraction (XRD), and catalytic experiments were carried out. The photocatalysis of the prepared catalyst in the degradation of tetracycline was investigated using persulfate (PS, Na 2 S 2 O 8 ) as a cocatalyst under visible light illumination. The above system can remove about 80% of tetracycline within 40 min. After three cyclic experiments, the material showed good recycling. According to material characterization and various experimental results, the enhanced performance of the material was attributed to the reduction of the recombination efficiency of photogenerated e - and h + , and activated persulfate to produce a large number of free radicals such as O 2 •- , SO 4 •- and 1 O 2 produced by the active sites provided by the catalyst's high specific surface area.