A Janus Fe‐SnO 2 Catalyst that Enables Bifunctional Electrochemical Nitrogen Fixation

Electrochemical N 2 reduction reactions (NRR) and the N 2 oxidation reaction (NOR), using H 2 O and N 2 , are a sustainable approach to N 2 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‐SnO 2 was designed as a Janus electrocatalyst for achieving highly efficient NRR and NOR catalysis. A high NH 3 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 NO 3 − 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 N 2 molecules, lowering the energy barrier for the vital breakage of N≡N and resulting in the enhanced N 2 fixation performance.