Efficient peroxymonosulfate activation by CuO-Fe2O3/MXene composite for atrazine degradation: Performance, coexisting matter influence and mechanism

CuO-Fe2O3/MXene was fabricated using a rapid microwave hydrothermal method and used for the enhanced peroxymonosulfate (PMS) activation and atrazine (ATZ) degradation. The ATZ degradation rate could reach up to nearly 100% within 60 min at pH = 6.4, with low dosage for CuO-Fe2O3/5% MXene (0.1 g.L-1) and PMS (0.37 mM). Experimental results and DFT calculations showed that coexisting matter had little influence on ATZ degradation at low concentrations, indicating the excellent anti-interference capability of the system. Circulation and interaction of Fe(III)/ Fe(II) and Cu(II)/ Cu(I) produced SO4 center dot- and center dot OH, O* and SO5 center dot- could participate in the formation of O-1(2). Then, ATZ degradation pathways, including dealkylation, dichlorination-hydroxylation, alkyl hydroxylation, alkyl oxidation, olefination, and deamination-hydroxylation processes, were proposed based on DFT calculations and ESI-QTOF-MS/MS data. QSAR analysis illustrated that most intermediates were more environmentally friendly than ATZ. This study developed novel materials with superior catalytic performance for elimination of refractory organic pollutants in wastewater.