Electrocatalytic nitrogen reduction reaction (NRR) at ambient conditions holds great promise for sustainably synthesizing ammonia (NH₃), while developing highly-efficient, long-term stable, and inexpensive catalysts to activate the inert NN bond is a key scientific issue. In this work, on the basis of the concept “N-heterocyclic carbenes (NHCs)”, we propose a carbon decorated graphitic-carbon nitride (C/g-C₃N₄) as novel metal-free NRR electrocatalyst by means of density functional theory (DFT) computations. Our results reveal that the introduced C atom in g-C₃N₄ surface can be regarded as NHCs and catalytic sites for activating NN bond, and are stabilized by the g-C₃N₄ substrate due to sterically disfavored dimerization. Especially, this NHCs-based heterogeneous catalysis can efficiently reduce the activated N₂ molecule to NH₃ with a low overpotential of 0.05 V via an enzymatic mechanism. Our work is the first report of NHCs-based electrocatalyst for N₂ fixation, thus opening an alternative avenue for advancing sustainable NH₃ production.

在环境条件下进行电催化氮还原反应（NRR）具有可持续合成氨（NH ₃）的广阔前景，同时开发高效，长期稳定且价格低廉的催化剂来活化惰性N N键是一个关键的科学问题。在这项工作中，基于“ N-杂环卡宾（NHCs）”的概念，我们通过密度泛函理论提出了一种碳装饰的石墨碳氮化物（C / gC ₃ N ₄）作为新型无金属NRR电催化剂。 （DFT）计算。我们的结果表明，在gC ₃ N ₄表面引入的C原子可被视为NHC和激活N N键的催化位点，并被gC ₃稳定。N ₄底物由于空间不利的二聚作用。特别地，这种基于NHCs的异质催化可以通过酶促机理将活化的N ₂分子有效地还原为NH _3，且低过电势为0.05V。我们的工作是有关NHC固定N ₂的基于NHCs的电催化剂的第一份报告，从而为促进可持续的NH ₃生产开辟了另一条途径。