Activation of peroxymonosulfate by tannin-derived porous carbon for enhanced bisphenol A degradation: Synergistic effect of surface nitrogen and oxygen functional groups

Abstract

Heteroatom-doped porous carbon materials hold considerable potential in activating peroxymonosulfate (PMS) for environmental remediation. To fabricate highly efficient and cost-effective catalysts, renewable tannin was co-pyrolyzed with urea to achieve both efficient nitrogen doping and oxygen self-doping. The synergetic effect of N and O functional groups, combined with a well-developed porous structure, resulted in the development of N-enriched, O-functionalized porous carbon materials (NOPC) that exhibit exceptional catalytic activity in PMS activation for bisphenol A (BPA) degradation. As for the optimized NOPC-700/PMS system, the removal efficiency of BPA can reach up to 97.2% with a TOC removal efficiency of 78%. Control experiments, characterization results, and DFT calculations confirmed the prominent contribution of both the graphitic N and carbonyl group (CO) to the catalytic performance of NOPC. In addition, the applicability of NOPC was evaluated via varying influential factors, changing the targeted organic pollutant, and altering the water matrix. Furthermore, it was found that the main ROSs generated from PMS activation could be altered by incorporating N into the carbon catalysts. Overall, this work will provide a straightforward approach to designing highly efficient carbon catalysts with great potential in catalytic AOPs for wastewater treatment.