Visible-light-assisted PMS activation by heterojunction photocatalyst MgIn2S4/Bi2O3 for tetracycline degradation

Composite MgIn 2 S 4 /Bi 2 O 3 was prepared and applied to the photocatalytic degradation of tetracycline (TC) under visible light. Results showed that formation of type-II heterojunction extended the visible light response range of the composite to 628 nm, effectively limiting the rapid recombination of photogenerated carriers. Further, the degradation experiment showed that TC was effectively decomposed by the composite. The main active substances for degrading TC were SO 4 · − , ·OH, h + and 1 O 2 . Cycling experiments showed that the TC removal rate by MgIn 2 S 4 /Bi 2 O 3 photocatalytic material was still as high as 75% after 4 cycles without any obvious changes in the crystalline phase structure.