Development of MoS2-stainless steel catalyst by 3D printing for efficient destruction of organics via peroxymonosulfate activation

Herein, a novel MoS 2 -stainless steel composite material was first synthetized via a 3D printing method (3DP MoS 2 -SS) for peroxymonosulfate (PMS) activation and organics degradation. Compared with MoS 2 -SS powder/PMS system (0.37 g/(m 2 /min)), 4.3-fold higher k FLO /S BET value was obtained in 3DP MoS 2 -SS/PMS system (1.60 g/(m 2 /min), resulting from the superior utilization of active sites. We observed that 3DP MoS 2 -SS significantly outperformed the 3DP SS due to the enhanced electron transfer rate and increased active sites. Moreover, Mo 4+ facilitated the Fe 2+ /Fe 3+ cycle, resulting in the rapid degradation of florfenicol (FLO). Quenching experiments and electron paramagnetic resonance spectra indicated that •OH, SO 4 • − , O 2 • − and 1 O 2 were involved in the degradation of FLO. The effect of influencing factors on the degradation of FLO were evaluated, and the optimized degradation efficiency of 98.69% was achieved at 1 mM PMS and pH of 3.0. Six degradation products were detected by UPLC/MS analyses and several possible degradation pathways were proposed to be the cleavage of C-N bonds, dechlorination, hydrolysis, defluorination and hydroxylation. In addition, 3DP MoS 2 -SS/PMS system also demonstrated superior degradation performance for 2-chlorophenol, acetaminophen, ibuprofen and carbamazepine. This study provided deep insights into the MoS 2 -SS catalyst prepared by 3DP technology for PMS activation and FLO-polluted water treatment.