Electronic Modulation of the Interaction between Fe Single Atoms and WO2.72-x for Photocatalytic N2 Reduction

In the design of photocatalysts for ammonia synthesis, the construction of effective nitrogen (N-2) adsorption and activation sites is critical. Herein, Fe single atoms were effectively fixed on the surfaces of WO2.72-x nanowires. Electronic interactions between single Fe atoms and WO2.72-x resulted in a d-band center shift toward the Fermi level and thus enhancement of N-2 bonding with the catalyst surface. The studies of differential charge density and electron localization reveal that there is enhanced electron transfer from Fe-SA/WO2.72-x to the adsorbed N-2, signifying that Fe single atoms are active centers for N-2 activation. Benefiting from electronic interactions, the optimized catalyst shows a NH(4)( )(+)generation rate of 186.5 mu mol g(-1 )h(-1) during photocatalytic N-2 reduction.