Degradation of tetracycline by MIL-101(Fe)/CoFe2O4 activated persulfate under visible light

Composites of MIL-101(Fe)/CoFe 2 O 4 were prepared by a simple solvothermal approach and these composites were explored for tetracycline (TC) degradation by using light and persulfate (PS). MIL-101(Fe)/CoFe 2 O 4 catalyst showed superior catalytic performance when combined with photocatalysis and chemical catalysis. Experimental results suggest that the degradation efficiency reached 83% within 40 min. The TC adsorption ability of MIL-101(Fe)/CoFe 2 O 4 was tightly associated with pH, which can be interpreted through isoelectric point. Oxygen-active species, containing singlet oxygen ( 1 O 2 ) or superoxide radicals (O· 2‾), were also generated when there was dissolved oxygen, which could decompose the TC organic contaminant in solution. To be specific, MIL-101(Fe)/CoFe 2 O 4 /PS/Vis catalytic system was capable of eliminating TC through forming h + , 1 O 2 , O· 2‾, hydroxyl radicals (·OH) and sulfate radicals (·SO 4 ‾) species. Moreover, MIL-101(Fe)/CoFe 2 O 4 composite material showed outstanding stability.