Insight into activation of peroxymonosulfate by Fe2O3 and MoN co-doped nitrogen-rich carbon to removal of bisphenol A: Singlet oxygen and electron transfer

Abstract

In this study, zeolite imidazolate framework-8 (ZIF-8) was utilized as a nitrogen-rich porous carbon substrate (NC) loaded with Fe2O3 and MoN to prepare bimetallic nanocatalysts (FeMo@NC) with synergistic catalytic effect. The optimized Fe0.05Mo0.05 @NC exhibited excellent performance in activating PMS and could completely remove BPA from water within 60 min. The results showed that the introduction of molybdenum significantly lowered the energy barrier for the generation of 1O2 and significantly increased the degree of graphitization and specific surface area of the catalysts, which facilitated the direct electron transfer and adsorption of target substances. The electron transfer of the surface complexes and 1O2 jointly induced the non-radical oxidation of BPA. In addition, the system was suitable for a wide pH range (pH=3–9) and resistant to background organic matter in wastewater. Our work elucidated the mechanism of transition metal Mo to enhance the catalytic performance of heterogeneous iron-based catalysts, which provided a new aspect for the development of catalysts with high efficiency for PMS activation.