Modulation of Single‐Iron‐Atom Coordination Environment Toward Three‐Electron Oxygen Reduction for Photocatalytic CH4 Conversion to CH3OH

Abstract By modifying the coordination environment of single‐Fe‐atom active site, effective regulation of the photocatalytic oxygen reduction pathway can be achieved to attain high activity for photocatalytic oxidation of CH 4 to CH 3 OH in an aqueous solution. A comprehensive investigation is conducted to study the impact of different coordination numbers of single Fe atoms on photocatalytic CH 4 oxidation reaction over carbon nitride. Among which, Fe 1 /C 3‐x N 4 with a Fe‐N3 coordination exhibit an exceptional photocatalytic performance in CH 4 oxidation, reaching a remarkable methanol yield of 928.27 µmol g cat −1 , much higher than Fe 1 /C 3 N 4 and Fe 1 /C 3 N 4‐x (308.47 and 473.26 µmol g cat −1 , respectively). Based on a collection of in situ characterizations and time‐dependent density functional theory calculations, it is determined that Fe 1 /C 3‐x N 4 with an optimal coordination number possesses the optimized electronic configuration that enables three‐electron oxygen reduction to generate hydroxyl radicals for photocatalytic conversion of CH 4 to CH 3 OH.