Iron- and nitrogen-rich Enteromorpha-derived dual-atom catalysts modified by clusters for the activation of peroxymonosulfate: Enhanced performance and synergistic mechanism

Catalysts have a wide range of applications in the efficient activation of peroxymonosulfate-based advanced oxidation processes (PMS-AOPs). To overcome the issues caused by the proportionality limitations of single atom catalysts as well as the high cost and difficulty in preparing atomic scale catalysts, this work innovatively introduced Co into Fe- and N-rich biomass (Enteromorpha) to rapidly synthesize a series of FeCo dual-atom catalysts modified by clusters (FeCo-NOC), achieving efficient activation of peroxymonosulfate (PMS). Compared with Fe-NC, the introduction of Co significantly increased the defect sites, porous structures, N content, and active sites of FeCo-NOC, thereby enhancing the removal rate of Diatrizoate (DTZ) by 59.64% to 70.09% using FeCo-NOC/PMS system. Moreover, FeCo-NOC/PMS system exhibited excellent anti-interference performance towards pH and coexisted matters and demonstrated outstanding stability in cyclic experiments. DTZ was removed through a nonradical pathway dominated by 1O2, with contributions from radicals such as SO-center dot 4 , center dot OH, center dot O-2, and electron transfer. Density functional theory calculations indicated that clusters effectively modulated the charge distribution of the dual-atom sites, promoting electron donation from the active sites to PMS and driving its decomposition into reactive oxygen species. This study provides an efficient synthesis strategy for high-performance catalysts from waste biomass for the efficient treatment of organic pollutants in water.