Synthesis of template-free magnetite nanospheres grown on Sb2WO6 hierarchical structures for sunlight-driven photo-Fenton catalysis of organic pollutants

Abstract

The effective management of low-concentration dye pollutants is a challenging task. Among various strategies, the Fenton reaction has emerged as a powerful approach for the degradation of dyes, particularly in the presence of highly efficient catalysts. This study presents the utilization of antimony tungstate nest modified small magnetite nanospheres (Fe₃O₄/Sb₂WO₆) as a heterostructure catalyst for the photo-Fenton mineralization of low-concentration organic pollutants, exemplified by methylene blue (MB) at ppm levels. The synthesis of Fe₃O₄/Sb₂WO₆ involves the in situ co-precipitation of agglomerated Fe₃O₄ nanospheres on hierarchical Sb₂WO₆ nests. The resulting Fe₃O₄/Sb₂WO₆ catalyst exhibits exceptional catalytic efficiency, demonstrating its capability to efficiently decontaminate low-concentration MB wastewater. Kinetics analysis reveals that the photo-Fenton-like mineralization route adheres to the first-order reaction kinetic model, and approximately 100% mineralization of MB is achieved with a minimal catalyst amount of 4 mg L⁻¹. The straightforward preparation and outstanding performance of Fe₃O₄/Sb₂WO₆ position it as a promising candidate for the removal of dye pollutants.