Programmable Control Over Radical and Non‑Radical Pathways in Fenton‑Like Catalysis via Carbon‑Encapsulated Iron...

Area of Science:

• Catalysis
• Environmental Chemistry
• Materials Science

Background:

• Fenton-like reactions present challenges in regulating synergistic radical and nonradical pathways for efficient pollutant degradation.
• Existing catalytic systems often lack programmable pathway switching capabilities, limiting their adaptability.

Purpose of the Study:

• To design and synthesize novel carbon-encapsulated iron-based core-shell catalysts.
• To elucidate the regulatory mechanisms governing pathway selection in Fenton-like reactions.
• To achieve programmable control over catalytic oxidation pathways for enhanced pollutant removal.

Main Methods:

• Synthesis of carbon-encapsulated iron-based core-shell catalysts with controlled geometry and encapsulation.
• Investigation of key factors influencing catalytic pathways: Fe/N sites, carbon geometry, oxidant properties, and pH.
• Identification of a proton-coupled electron transfer mechanism involving H+/OH- ions.

Main Results:

• Discovered that iron and carbon precursors precisely regulate catalyst structure and encapsulation.
• Revealed universal mechanisms where Fe/N sites, carbon geometry, oxidant structure, and pH act as pathway switches.
• Established that cooperative tuning of carbon work function and iron d-band center dictates pathway selection based on oxidant frontier orbitals.

Conclusions:

• The study provides a rational design principle for adaptive catalytic oxidation in Fenton-like systems.
• Developed catalysts enable programmable directional catalysis, bridging the gap left by single-pathway designs.
• Understanding the dominant catalytic mechanism is crucial for controlling organic pollutant transformation.