Regulating electron distribution of Fe/Ni-N4P2 single sites for efficient photo-Fenton process

Regulating local electron density by introducing single-atom is an effective strategy to improve the activity of heterogeneous photo-Fenton processes. Here N, P coordinated Fe and Ni single-atom catalysts on carbon nitrides (CN-FeNi-P) were prepared to activate H2O2 for contaminant mineralization under visible light irradiation. The as-prepared CN-FeNi-P presented a higher moxifloxacin degradation activity in photo-Fenton system, which was up to 3.7 times that of pristine CN, meanwhile, its TOC removal reached to 95.9 % in 60 min. Based on density functional theory calculations, the Ni single-atoms serve as the optimal reactive sites to produce center dot OH. The strong interaction between Fe and Ni single-atoms by P-bridging and the modulated local electron structure after introducing P into coordination environment can lower center dot OH formation energy. This study provides new doping strategies to design single-atom catalysts and expands the family of the Fenton-like system for advanced oxidation technologies.

Automated summary

Regulating local electron density by introducing single-atom is an effective strategy to improve the activity of heterogeneous photo-Fenton processes. In this study, N, P coordinated Fe and Ni single-atom catalysts on carbon nitrides (CN-FeNi-P) were prepared and used to activate H2O2 for contaminant mineralization. The results showed that CN-FeNi-P exhibited significantly higher moxifloxacin degradation activity compared to pristine CN, with a TOC removal of 95.9% in 60 minutes. Density functional theory calculations revealed that Ni single-atoms served as the optimal reactive sites for producing center dot OH. The strong interaction between Fe and Ni single-atoms by P-bridging and the modulated local electron structure after introducing P into the coordination environment contributed to lower center dot OH formation energy.