Sulfidation modified Fe3O4 nanoparticles as an efficient Fenton-like catalyst for azo dyes degradation at wide pH range

The application of a novel sulfidation modified Fe3O4 nanoparticles (S-Fe3O4NP) as catalyst for degradation of dyes-containing wastewater through Fenton-like reaction is investigated in the current research. Results demonstrate the as-prepared S-Fe3O4NP is mainly composed of interconnected FeS2 and sulfur-doped Fe3O4, which can be recovered from aqueous solution by magnetic separation method. S-Fe3O4NP/H2O2 catalytic system exhibits great advantage and much higher catalytic performance over Fe3O4 based Fenton-like process, which can effectively degrade RhB at wide pH range from 3 to 9. It also presents excellent recyclability in the first three cycles and high catalytic activity towards degradation of various azo dyes such as MB, MG and AR-73. The H+ species, Fe2+ ions and surface Fe2+ active sites generated in the S-Fe3O4NP/H2O2 system can significantly facilitate the production of hydroxyl radicals and this synergetic effect between FeS2 and sulfur-doped Fe3O4 leads to the enhanced catalytic performance of S-Fe3O4NP. (C) 2020 Elsevier B.V. All rights reserved.