Facile synthesis of Co, Fe-bimetallic MIL-88A/microcrystalline cellulose composites for efficient adsorptive and photo-Fenton degradation of RhB dye

Photo-Fenton technology is effective in treatment of dye containing effluents in water under visible light illumination. The present article reports fabrication of a considerably efficient photo-Fenton catalytic system, the Co, Fe-MIL88/MCC composite, by a mild hydrothermal method. The composite containing bimetals Co2+/Co3+ and Fe2+/Fe3+ ions with coordination environments used as activators of H2O2-assited visible light photo-Fenton degradation of RhB. The effects of initial pH, catalyst dosage and H2O2 concentration on RhB decomposition were explored. Nearly 87% of RhB molecule was removed within 100 min in the Co, Fe-MIL88/MCC/H2O2/Visible system ana maintain the recyclability rate of more than 82.2% after five successive cycles. The photoinduced •O2− and •OH plays a major role in efficient removal of RhB. The excellent catalytic performance of the composite can be credited to the proficient electrons transfer by Fe2+/Fe3+ and Co2+/Co3+ redox cycles, activation of H2O2 by photoexcited electrons to generate •OH. As well, the optimal Co, Fe-MIL88 (Co/Fe in ratio 1/2 wt%)/MCC composite exhibited good recyclability and stability.