Fe-VS Electrocatalyst with Organic Matrix-Mediated Electron Transfer for Highly Efficient Nitrogen Fixation.

Electrochemical N fixation is considered to be a promising alternative to Haber-Bosch technology. Inspired by the composition and structure of natural nitrogenase, Fe-doped VS nanosheets were prepared via one-step solvothermal method. The electron transfer system mediated by organic conductive polymer (1-AAQ-PA) was constructed to promote the electron transfer between Fe-VS nanosheets and the electrode in electrocatalytic N reduction reaction (NRR). The obtained 1-AAQ-PA-Fe-VS electrode converted N to NH with a yield of 31.6 μg h  mg at -0.35 V vs. reversible hydrogen electrode and high faradaic efficiency of 23.5 %. The introduction of Fe dopants favored N adsorption and activation, while the Li-S bond between Fe-VS and Li SO effectively inhibited hydrogen evolution. The highly efficient electron utilization in the electrocatalytic NRR process was realized using the 1-AAQ-PA as the electron transfer medium. Density functional theory calculations showed that N was preferentially adsorbed on Fe and reduced to NH via both distal and alternating mechanism.