Improvement Catalytic Efficiency of the Fenton-Like Reaction via the Interaction among Fe Species Encapsulated in N-Doped Carbon Materials

The Fenton-like reaction has been widely used for environmental modification. However, improvement of the catalytic efficiency is still a challenge. In this study, a series of core–shell-shaped catalysts (FeNC- x, x presents the calcination temperature) for the Fenton-like reaction was fabricated through the pyrolysis of the Fe-based metal–organic frameworks (Fe-MOF). The Fe species were encapsulated by the N-doped carbon materials and changed from Fe 3 O 4 to Fe 3 C, α-Fe, and Fe–N 4 with the temperature increasing from 500 to 800 °C. Simultaneously, the electron density of the Fe atom obviously increased. FeNC-650 exhibited high efficiency, as more than 85.6% TC (40 mg/L) instantaneous removal through the H 2 O 2 -based Fenton-like reaction. The turnover number is about 70 and 64 times higher than that of Fe-MOF and FeNC-500. The synergistic interaction among Fe 3 C, α-Fe, and Fe–N 4 induced electron distribution around the Fe atom and excellent catalytic performances. Moreover, FeNC-650 exhibited excellent interference resistance toward different anions and humic acid. The toxicity of intermediate products decreased during the TC degradation. This research may give a strategy for the synthesis of catalysts used in wastewater purification.