一氧化氮（NO）通常来自汽车尾气和工业烟气，是最严重的空气污染物之一。为解决这一问题，电催化一氧化氮还原反应（NORR）被提出，其不仅能去除NO大气污染物，还能产生有价值的氨（NH₃）。因此，通过对Fe₃C纳米晶体进行改性，制备的Fe₃C/C-900样品在常温常压条件下可作为高效NORR催化剂。电化学测试结果表明，Fe₃C/C-900催化剂在–0.8 V（vs RHE）时的合成NH₃法拉第效率为76.5 %，在–1.2 V（vs RHE）时的NH₃产率为177.5 μmol·h^–1·cm^–2。同时，其在长时间电解过程中，也能保持稳定的NORR活性。此外，我们将Fe₃C/C-900的高NORR特性归因于两个方面：一方面，Fe₃C纳米晶体的内在活性，包括降低决速步骤（*NOH→*N）能垒和抑制氢析出副反应；另一方面，多孔碳基底有利于活性成分的分散、气态NO反应物的有效吸附和液态NH₃产物的释放。

Nitric oxide (NO), which generally originates from vehicle exhaust and industrial flue gases, is one of the most serious air pollutants. In this case, the electrochemical NO reduction reaction (NORR) not only removes the atmospheric pollutant NO but also produces valuable NH₃. Hence, through the synthesis and modification of Fe₃C nanocrystal catalysts, the as–obtained optimal sample of Fe₃C/C–900 was adopted as NORR catalyst at ambient conditions. As a result, the Fe₃C/C–900 catalyst showed an NH₃ Faraday efficiency of 76.5 % and an NH₃ yield rate of 177.5 μmol·h^–1·cm^–2 at a working potential of –0.8 and –1.2 V versus reversible hydrogen electrode (vs RHE), respectively. And it delivered a stable NORR activity during the electrolysis. Moreover, we attribute the high NORR properties of Fe₃C/C–900 to two aspects: one is the enhanced intrinsic activity of Fe₃C nanocrystals, including the lowering of the energy barrier of rate–limiting step (*NOH→*N) and the inhibition of hydrogen evolution; on the other hand, the favorable dispersion of active components, the effective adsorption of gaseous NO, and the release of liquid NH₃ products facilitated by the porous carbon substrate.