摘要
The increasing environmental impact of wastewater pollution and the growing demand for clean water highlight the need for innovative and efficient catalysts to degrade harmful organic contaminants. This research addresses the limitations of conventional Fe2O3-based photo-Fenton catalysts and the complex synthesis of heterostructured systems combining semiconductor photocatalysts and Fe-based catalysts. We developed a dual-functional, single- component hexagonal iron borate (FeBO3) catalyst, designed to harness visible solar radiation and drive Fenton oxidation in wastewater treatment. The synthesis of the FeBO3 was systematically optimized by varying the Fe precursors, Fe content, and calcination temperatures, resulting in nanoparticles of similar to 400 nm and hexagonal structures of 2.8 mu m when a hydrothermal process was applied. The optimized FeBO3 possessed a bandgap of 2.42 eV, facilitating efficient absorption of solar irradiation and a rapid and sustainable photo-Fenton reaction. Under simulated solar conditions, the catalyst achieved an exceptional methylene blue (MB) degradation rate constant of 1.07 min(-1) , outperforming conventional iron oxides (Fe2O3 and Fe3O4) by 300- to 1200-fold. This remarkable enhancement is attributed to the synergistic effects of the FeBO3 catalyst, where photogenerated electrons promote the Fe3+/Fe2+ redox cycling. The catalyst showed a 238-fold reduction in degradation rate when compared to the reaction in the absence of solar irradiation, emphasizing the critical role of light. Trapping experiments identified hydroxyl radicals (center dot OH) as the dominant reactive oxygen species (ROS). Further examination confirmed the catalyst's structural stability, and sustained catalytic efficiency over five cycles, with minimal Fe leaching.