A Janus Fe‐SnO₂Catalyst that Enables Bifunctional Electrochemical Nitrogen Fixation

Abstract

Electrochemical N₂ reduction reactions (NRR) and the N₂ oxidation reaction (NOR), using H₂ O and N₂ , are a sustainable approach to N₂ fixation. To date, owing to the chemical inertness of nitrogen, emerging electrocatalysts for the electrochemical NRR and NOR at room temperature and atmospheric pressure remain largely underexplored. Herein, a new-type Fe-SnO₂ was designed as a Janus electrocatalyst for achieving highly efficient NRR and NOR catalysis. A high NH₃ yield of 82.7 μg h^-1 mg_cat. ^-1 and a Faraday efficiency (FE) of 20.4 % were obtained for NRR. This catalyst can also serve as an excellent NOR electrocatalyst with a NO₃ ^- yields of 42.9 μg h^-1 mg_cat. ^-1 and a FE of 0.84 %. By means of experiments and DFT calculations, it is revealed that the oxygen vacancy-anchored single-atom Fe can effectively adsorb and activate chemical inert N₂ molecules, lowering the energy barrier for the vital breakage of N≡N and resulting in the enhanced N₂ fixation performance.