Boosted adsorption and oxidation performances in peroxymonosulfate (PMS)-based heterogeneous fenton-like reactions via P, N co-doping strategy

Abstract

The heterogeneous Fenton-like reactions (HTFR) have attracted considerable interest for their efficacy in degrading pollutants. However, the development of effective strategies for enhancing performance in HTFR remains a subject of ongoing research. Herein, a synergistic adsorption and oxidation-dominated process was developed to overcome the bottlenecks of peroxymonosulfate (PMS)-based HTFR in terms of mass transfer and catalyst reactivity. Heteroatom (P, N) co-doping for manganese (Mn) was employed to fabricate an efficient catalyst, Mn@5-NPC-800, which exhibited exceptional abilities of adsorption and PMS activation. The enhanced performance of HTFR was attributed to the increased specific surface area (SSA) and enhanced yields of graphitic-N/MnIII of the catalyst, which facilitated reactant enrichment and electron transfer in the delocalized conjugated area, respectively. The PMS-based HTFR induced by Mn@5-NPC-800 for pollutant removal was characterized by a synergistic adsorption and reactive oxygen species (ROS)-dominated oxidation process. DFT calculations revealed that the N, P co-doped carbon matrix (NPC) acted as a conductive bridge, significantly improving electron transfer between MnP and PMS molecule, which was identified as a key factor in governing the catalytic performance. The investigation presents a suggestive example of employing a doping strategy to create a synergistic effect of adsorption and oxidation, thereby strengthening the performance of Fenton-like reactions.