Activation of Na2S2O8 by MIL-101(Fe)/Co3O4 composite for degrading tetracycline with visible light assistance

MIL-101(Fe)/Co3O4 composites were synthesized using a facile solvothermal method to establish the superiority of a heterogeneous photochemical catalysis system in the presence of Na2S2O8 with visible light irradiation. In the present system, the MIL-101(Fe)/Co3O4 catalyst showed better catalytic performance than the single pho-tocatalytic or chemical catalytic system, implying that the MIL-101(Fe)/Co3O4 catalyst can combine both pho-tocatalysis and chemical catalysis well. When tetracycline (TC) is the target pollutant, the highest degradation efficiency can be achieved within 40 min, reaching to 86 %. Crystallinity, morphology, and elemental valence of the MIL-101(Fe)/Co3O4 composite were explored by using X-ray diffraction (XRD), scanning electron microscopy (SEM) as well as X-ray photoelectron spectroscopy (XPS). From the quenching experiments, it was found that O-1(2) , (SO4-)-S-center dot, 'OH, and O-2(-) make contributions to the effective removal of tetracycline. Apart from that, the re-covery and reuse characteristics of MIL-101(Fe)/Co3O4 may facilitate the sustainable wastewater treatment.