Mechanistic investigation of rapid catalytic degradation of tetracycline using CoFe2O4@MoS2 by activation of peroxymonosulfate

Abstract

A one-pot hydrothermal synthesis strategy was used to successfully prepare a series of Fenton-like catalysts based on the loading of CoFe2O4 nanoparticles on the surface of MoS2. By activating peroxymonosulfate (PMS), it was found that the as-prepared CoFe2O4@MoS2 catalysts with different mass ratios of CoFe2O4 and MoS2 all exhibit superior catalytic ability for tetracycline (TC) degradation. The degradation efficiency of TC was greatly improved because of the synergetic effect of the highly active Mo(IV) sites and unsaturated S on the surface of the catalyst, which could efficiently accelerate the circulation of Fe(III) to Fe(II) and significantly accelerate the adsorption and decomposition of PMS. The EPR and quenching experimental results revealed that 1O2 was detected as the main active species for TC degradation in the CoFe2O4@MoS2/PMS system. Furthermore, the possible TC degradation pathways wase proposed and the toxicity estimation of intermediates was evaluated by Toxicity QSAR prediction. Our work provides a new strategy to fabricate transition-metal-based catalysts for more efficiency in PMS activation.