Visible light promoted Fe3S4 Fenton oxidation of atrazine

We demonstrate that visible light irradiation can promote Fe 3 S 4 Fenton oxidation of atrazine. The visible light irradiation could increase the atrazine Fenton degradation rate by 4.9 times. The enhanced atrazine degradation activity under visible light was attributed to the higher surficial Fe(II)/Fe(III) ratio of Fe 3 S 4 and the efficient surface iron redox cycle triggered by visible light. Experimental results revealed that the operando formation of FeOOH on the Fe 3 S 4 surface blocked the iron redox cycle and inhibited the H 2 O 2 decomposition, accounting for the largely decreased Fenton activity of Fe 3 S 4 in dark, while these problems were successfully solved by the introduction of visible light irradiation, which excite Fe 3 S 4 to produce abundant photo-generated electrons and O 2 − for efficient regeneration of active Fe(II) species of Fe 3 S 4 and in-situ formed FeOOH.