Enhanced Degradation of Levofloxacin through Visible-Light-Driven Peroxymonosulfate Activation over CuInS 2 /g-C 3 N 4 Heterojunctions.

In this work, the heterojunctions of CuInS 2 embedded in the g-C 3 N 4 materials (xCuInS 2 /g-C 3 N 4 , abbreviated as xCIS/GCN) was successfully prepared for peroxymonosulfate (PMS) activation under visible light. The catalysts are characterized by different techniques, such as XRD, FTIR, SEM, TEM, and UV-vis. The unique heterojunction composites can suppress the recombination of photogenerated pairs. The catalytic results showed that the 3CIS/GCN exhibited excellent catalytic levofloxacin (LVF) degradation efficiency, while more than 98.9% of LVF was removed in 60 min over a wide pH range. SO 4 •- , O 2 •- , OH • , and 1 O 2 were verified as the main reactive species for LVF degradation via the quenching experiments and electron paramagnetic resonance technology (EPR). The synergetic effect of xCIS/GCN, PMS, and visible light irradiation was discussed. The possible LVF degradation pathway was proposed through byproducts analysis (LC-MS). Moreover, the 3CIS/GCN/vis-PMS system has very low metal leaching. Owing to xCIS/GCN having good properties for PMS activation, it has potential applications for LVF or other hazardous pollutants degradation.