Magnetic Co-doped 1D/2D structured γ-Fe2O3/MoS2 effectively activated peroxymonosulfate for efficient abatement of bisphenol A via both radical and non-radical pathways

Iron-based catalysts have been widely used to treat refractory organic pollutants in wastewater.In this paper,magnetic Co-γ-Fe2O3 was synthesized by a facile tartaric acid-assisted hydrothermal method,and Co-γ-Fe2O3/MoS2 nanocomposite catalyst was obtained via in situ growth of MoS2 nanosheets on Co-γ-Fe2O3 nanoparticles.The nanocomposite catalysts were used to decompose bisphenol A(BPA)by activating peroxymonosulfate(PMS).It was shown that only 0.15 g/L catalyst and 0.5 mmol/L PMS degraded 10 mg/L of BPA(99.3％within 10 min)in the pH range of 3-9.PMS was activated due to redox cycling among the pairs Co(Ⅲ)/Co(Ⅱ),Fe(Ⅲ)/Fe(Ⅱ),and Mo(Ⅵ)/Mo(Ⅳ).Quenching experiments and electron paramagnetic resonance spectroscopy demonstrated that both radical and non-radical pathways were involved in BPA degradation,in which active radical sulfate radical and non-radical singlet oxygen were the main reactive oxygen species.Ten intermediates were identified by liquid chromatography-coupled mass spectrometry,and three possible BPA degradation pathways were proposed.The toxicity of several degradation intermediates was lower,and Co-γ-Fe2O3/MoS2 exhibited excellent reusability and could be magnetically recovered.