Fe containing template derived atomic Fe-N-C to boost Fenton-like reaction and charge migration analysis on highly active Fe-N4 sites

Persulfate-based advanced oxidation processes are promising technologies to solve water pollution. In this work, single iron atoms are anchored on three-dimensional N-doped carbon nanosheets by a chemical vapor deposition (CVD) method with ferrocene-loaded CaO as the hard template. The high surface density of Fe-N-4 sites and abundant interconnected meso-macro pores are highly favorable for activating peroxymonosulfate (PMS) to produce superoxide radicals (O-2(-)), giving rise to ultrahigh activity and excellent stability for pollutant degradation. Experiment and density functional theory (DFT) calculations reveal that Fe-N-4 is the main active site, on which electrons transfer from C to Fe via the C-N-Fe bond to secure the low-valence state of Fe species for the redox process. This work proposes a new strategy for developing highly active single-atom materials by CVD and reveals mechanisms of PMS activation on single-atom activators.

Automated summary

This study successfully anchored single iron atoms on three-dimensional N-doped carbon nanosheets using a chemical vapor deposition method, forming high-density Fe-N-4 sites. These sites exhibit excellent activity and stability for activating peroxymonosulfate and producing superoxide radicals to degrade pollutants.