Confining FeNi nanoparticles in biomass-derived carbon for effectively photo-Fenton catalytic reaction for polluted water treatment

Photo-Fenton catalytic degradation organic contaminant is considered as a promising approach to water purification and environmental remediation. The novel class of photo-Fenton heterogeneous composite with large specific surface area, abundant active sites, uniform and stable metal ions, and fast Fe2+/Fe3+ conversion rate is considered as potential catalysts. Herein, a highly efficient and sustainable photo-Fenton heterogeneous composite (FeNi@corncob-activated carbon (CCAC)) was prepared by confining FeNi nanoparticles in CCAC through a simple solvothermal and activated-carbonization method. The porous structure and a high specific surface area of CCAC would effectively disperse FeNi nanoparticles, causing a significantly enhanced photo-Fenton catalytic performance. The RhB degradation rate of FeNi@CCAC was 2.3 times higher than that of FeNi. After five cycles, RhB degradation rate of FeNi@CCAC was barely decreased, confirming that FeNi@CCAC had high cyclability and reproducibility. Moreover, the reaction mechanism was analyzed in-depth via photoelectrochemical and electron spin resonance characterization. The outstanding results can be attributed to the contribution of the active species ‧OH, ‧O2–, and h+ in photo-Fenton degradation of RhB. Notably, FeNi@CCAC also has excellent photo-Fenton catalytic performance in sewage. This work illustrates a simple and effective method to improve the photo-Fenton catalytic reaction.Graphical abstractMOF-derived FeNi nanoparticles were confined in corncob-activated carbon to prepare a high-efficiency photo-Fenton heterogeneous composite for catalytic degradation of organic pollutants.