Facile Synthesis of Atomic Fe‐N‐C Materials and Dual Roles Investigation of Fe‐N₄ Sites in Fenton‐Like Reactions

Abstract

Fenton-like reactions with persulfates as the oxidants have attracted increasing attentions for the remediation of emerging antibiotic pollutions. However, developing effective activators with outstanding activities and long-term stabilities remains a great challenge in these reactions. Herein, a novel activator is successfully synthesized with single iron atoms anchored on porous N-doped carbon (Fe-N-PC) by a facile chemical vapor deposition (CVD) method. The single Fe atoms are coordinated with four N atoms according to the XANES, and the Fe-N 4 -PC shows enhanced activity for the activation of peroxymonosulfate (PMS) to degrade sulfamethoxazole (SMX). The experiments and density functional theory (DFT) calculations reveal that the introduction of single Fe atoms will regulate the main active sites from graphite N into Fe-N 4 , thus could enhance the stability and tune the PMS activation pathway from non-radical into radical dominated process. In addition, the N atoms connected with single Fe atoms in the Fe-N 4 -C structure can be used to enhance the adsorption of organic molecules on these materials. Therefore, the Fe-N 4 -C here has dual roles for antibiotics adsorption and PMS activation. The CVD synthesized Fe-N 4 -C shows enhanced performance in persulfates based Fenton-like reactions, thus has great potential in the environmental remediation field.

Nitrogen-doped 3D hollow carbon spheres for efficient selective oxidation of C–H bonds under mild conditions

“…The peak at 21.4° could be assigned to amorphous carbon, and the other two peaks are corresponding to the (002) and (100) characteristic planes of graphitic carbon. 22,41 The intensity ratio of the peaks at 26° and 21.4° gradually increases with the deposition temperature acceleration, indicating that the degree of graphitization is enhanced. The graphitization degree and defect levels of all samples were characterized by Raman spectrometer.…”

Multilayer Self‐Assemblies for Fabricating Graphene‐Supported Single‐Atomic Metal via Microwave‐Assisted Emulsion Micelle

“…X-ray absorption nearedge structure (XANES) spectrum of Fe-SA-NrGO suggested that Fe K-edge was located between FeO (Fe II ) and Fe 2 O 3 (Fe III ), which indicated that the oxidation valence of Fe in Fe-SA-NrGO ranged from +2 to +3 (Figure 3d). [21] Considering the position of the absorption edge, it was clear that the different light elements such as N/O coexistence were coordinated with single-Fe atoms. The Fourier-transformed k 3 -weighted extended X-ray absorption fine structure (EXAFS) image displayed two main peaks at 1.97 and 2.89 Å, which were assigned to the first coordination shell of FeN/O and second coordination shell of FeNC, respectively (Figure 3e and Figures S10 and S11, Supporting Information).…”

Insights into biochar supported atomically dispersed cobalt as an efficient peroxymonosulfate activator for sulfamethoxazole degradation: robust performance, ROS and surface electron-transfer pathways

“…Unlike conventional crystalline catalysis, atomically dispersed catalysts possess extensive catalytically active sites, 30,32 owing to the utmost atomic utilization, and thus the high metal loading often reflects the superior catalytic performance. 26 As shown in Fig.…”

“…The high defect level endows the catalyst with more active sites, and it facilitates the acquisition of electrons by electrophilic peroxides. 38,39 Unlike conventional crystalline catalysis, atomically dispersed catalysts possess extensive catalytically active sites, 30,32 owing to the utmost atomic utilization, and thus the high metal loading often reflects the superior catalytic performance. 26 As shown in Fig.…”

“…28 SACs can compensate well for conventional catalysts' deficiencies and break the barriers between homogeneous and heterogeneous catalysis. 29,30 Consequently, SACs are highly interesting in the SR-AOP field, 30 and multiple transition metal-based SACs have been reported, 30,31 including Mn, 27 Fe, 32 Co, 33 Ni, 10 and Cu. 29 Nevertheless, the preparation of most SACs requires expensive process equipment and tedious synthesis steps, and low yields often limit their application in large-scale environmental remediation.…”