Reconstructing the coordination environment of single atomic Fe-catalysts for boosting the Fenton-like degradation activities

Abstract

This study develops an advanced single-atomic iron-loaded graphitic carbon nitride (Fe1/CN) with unparalleled efficiency for converting peroxymonosulfate (PMS) to oxidants for water treatment. We found that acid-etching of Fe1/CN leads to the reconstruction of conventional Fe1–N4 to Fe1–C2N1 active sites. The acid-induced Fe1–C2N1 sites are more favorable for PMS binding and have a lower energy barrier for 1O2 production. The precise tuning of the coordination environment bestows the acid-etched Fe1/CN with 29 times higher rate constants of bisphenol A degradation than its pristine counterparts. Further, the particulate catalysts were assembled into a self-supported catalytic membrane, which demonstrates excellent long-term durability throughout 170 h flow-through tests in both synthetic and real wastewater. This work provides pivotal insights into improving PMS activation activity by regulating the coordination environment around single atomic Fe sites. The engineering innovation laid the groundwork for new point-of-use water treatment devices.