New strategy boosts iron-based single-atom catalysts for Fenton-like reactions

Researchers at China's Xinjiang Technical Institute of Physics and Chemistry have devised a novel core-shell confined iron-based single-atom catalyst. This innovative catalyst exhibits both high Fenton-like catalytic activity and remarkable structural stability, allowing for near-complete degradation of 2,4-dichlorophenol within just 20 minutes in mildly acidic conditions.

The breakthrough addresses the longstanding challenge of balancing activity and stability in iron-based single-atom catalysts used for water remediation. By strategically modifying the local coordination environments of iron atoms, the team managed to maintain high catalytic efficiency without sacrificing the catalyst's structural integrity.

The catalyst's success hinges on the precise arrangement of iron atoms within nitrogen-doped carbon shells, with each iron atom flanked by four nitrogen atoms. This configuration not only enhances reaction efficiency but also ensures the stable containment of iron atoms, preventing their leaching into the solution—an issue that typically leads to rapid catalyst degradation under harsh acidic environments.

Extensive testing revealed that the catalyst maintained over 95% pollutant removal efficiency over 10 consecutive reuse cycles, with virtually no iron leaching into the water. The degradation process primarily involved hydroxyl radicals, with singlet oxygen playing a secondary role. These findings, published in the Journal of Catalysis, provide valuable insights into the relationship between coordination symmetry and catalytic performance, paving the way for the development of highly efficient and durable iron-based single-atom Fenton-like catalysts.