Synthesis of Mackinawite (FeSm) and its heterogeneous Fenton-like catalytic degradation performance of rhodamine B

In this work, Mackinawite (FeS m ) was synthesized by homogeneous precipitation method, and flower-like nanoparticles formed by the aggregation of nanosheets with a preferred orientation along the (001) plane. The heterogeneous Fenton-like degradation performance of FeS m on rhodamine B (RhB) was investigated, results illustrated that RhB degradation was the synergistic effect of adsorption, Fenton, and a heterogeneous Fenton-like reaction. In repeated experiments, the reduction of reactivity was attributed to the oxidation of FeS m into lepidocrocite, whereas lepidocrocite has relatively low hydroxyl radicals (•OH) production reactivity. Thus, it showed excellent degradation effects in long-time degradation of RhB. Photoluminescence technology and free radical capture experiments demonstrated that •OH produced on the surface of catalyst was the main active species to remove RhB. In addition, the Fe species on the surface of FeS m was the main active center for surface-mediated reactions. A total organic carbon test revealed that the degradation was not complete and degradation intermediates were formed. Liquid chromatography-mass spectrometry technology was used to identify the degradation intermediates. On this basis, possible degradation pathways were proposed. Flower-like Mackinawite (FeS m ) nanoparticles were synthesized using an homogeneous precipitation method. FeS m was used as an heterogeneous Fenton-like catalyst to degrade RhB. The reduction of FeS m reuse activity was mainly attributed to the formation of lepidocrocite with lower activity. •OH surface-bounded of FeS m was the main active species for RhB degradation. The possible degradation pathway of RhB was speculated.