Efficient Fenton-like Degradation of Methylene Blue Using a Green-Synthesized MOF Catalyst

Water is essential for life; however, it is increasingly contaminated by organic dyes such as methylene blue (MB). This study presents a simple, rapid, and environmentally friendly method for synthesizing a high-quality iron-based metal-organic framework (Fe-MOF) catalyst. The MOF was prepared using water as the sole solvent under hydrothermal conditions relevant to industrial applications, completely eliminating the use of toxic organic solvents. The strategy employs organic salts instead of conventional protonated linkers, enhancing solubility and facilitating MOF formation. The resulting Fe-MOF exhibits a well-defined nanocrystalline structure, ordered microporosity, and minimal residual linker impurities. The material was characterized using FTIR, XRD, TGA, SEM, and UV-Vis spectroscopy. Its catalytic performance was evaluated for the Fenton-like degradation of MB. Systematic optimization of reaction parameters, including pH, catalyst dosage, H 2 O 2 concentration, and contact time, revealed optimal conditions of pH 9, 100 mg catalyst, 10 ppm MB, and 120 min reaction time, achieving a maximum degradation efficiency of 93.8% with a correlation coefficient of R 2 = 0.9944. The excellent catalytic activity is attributed to abundant active sites, a flexible framework structure, and efficient Fe 3+ /Fe 2+ redox cycling, which collectively enhance the generation of hydroxyl radicals (•OH), the primary reactive species responsible for dye degradation. This work demonstrates a green, sustainable, and highly efficient approach for wastewater treatment using a recyclable MOF-based catalyst.