Novel Wet Catalytic Elimination of Recalcitrant Azo Dyes from Contaminated Waters Using Fe 3 O 4 –CuO Nanoparticles Immobilized Over g-C 3 N 4 -Functionalized Canvas Fabric

This study investigates the catalytic efficiency of a novel heterogeneous catalyst, Fe3O4-CuO@g-C3N4/CF, for the degradation of dye-based pollutants. The active catalytic component comprises magnetic iron oxide, copper oxide (Fe3O4-CuO), and graphitic carbon nitride (g-C3N4) immobilized on a canvas fabric (CF) support. The fabrication process involved the ultrasonic deposition of g-C3N4 onto the CF substrate, followed by the incorporation of Fe3O4-CuO nanoparticles. The physicochemical characterization of synthetized materials was performed using FTIR, SEM, XRD, and TGA. The catalytic activity of the synthetized material was evaluated during the wet catalytic oxidation of methylene blue (MB) using H2O2. As a result, a 98.5% removal of MB was achieved within 40 min using an exposed surface area of 4 cm2. The synthesized composite demonstrated excellent reusability, maintaining high catalytic efficiency over five successive reused cycles without a significant loss in its performance. Mechanistic analysis revealed that superoxide (O2•-) and hydroxyl (•OH) radicals were the dominant reactive oxygen species (ROS) driving the oxidation process. Finally, the findings highlight the potential use of Fe3O4-CuO@g-C3N4-CF as a stable and efficient catalyst for the elimination of dyes from contaminated waters.