Nano-Fe⁰ embedded in N-doped carbon architectures for enhanced oxidation of aqueous contaminants

Abstract

Nano-Fe⁰ embedded in N-doped carbon architectures (Fe⁰@N-C) were used as a peroxymonosulfate (PMS) activator for the mineralization of organic pollutants. Fe⁰@N-C was synthesized through a MOF-mediated recrystallization approach. Fe⁰@N-C exhibited high activity and reusability, better than that of most conventional metal catalysts. Further, the influences of some representative factors for the PMS activation were comprehensively analyzed and optimized. The enhanced performance of Fe⁰@N-C was primarily ascribed to abundant reactive oxygen species, especially ¹O₂, released in the oxidation process at the solid/aqueous interface. Nano-Fe⁰ wrapped with N-doped graphitic layers could preferentially generate effective Fe⁰ and Fe-Nₓ active sites with the electronic structure reconstruction, endowing the outstanding catalytic activity. The unique porous carbon structure not only protected the embedded nano-Fe⁰ from poisoning or leaching, but also provided suitable mass transfer channels and also promoted electron tunneling efficiency. These outstanding characteristics manifested Fe⁰@N-C had promising potential for organic pollutant degradation.