Direct Eight-Electron N 2 O Electroreduction to NH 3 Enabled by an Fe Double-Atom Catalyst.

N 2 O is a dominant atmosphere pollutant, causing ozone depletion and global warming. Currently, electrochemical reduction of N 2 O has gained increasing attention to remove N 2 O, but its product is worthless N 2 . Here, we propose a direct eight-electron (8 e ) pathway to electrochemically convert N 2 O into NH 3 . As a proof of concept, using density functional theory calculation, an Fe 2 double-atom catalyst (DAC) anchored by N-doped porous graphene (Fe 2 @NG) was screened out to be the most active and selective catalyst for N 2 O electroreduction toward NH 3 via the novel 8 e pathway, which benefits from the unique bent N 2 O adsorption configuration. Guided by theoretical prediction, Fe 2 @NG DAC was fabricated experimentally, and it can achieve a high N 2 O-to-NH 3 Faradaic efficiency of 77.8% with a large NH 3 yield rate of 2.9 mg h -1 cm -2 at -0.6 V vs RHE in a neutral electrolyte. Our study offers a feasible strategy to synthesize NH 3 from pollutant N 2 O with simultaneous N 2 O removal.