Abstract Although electrocatalytic nitrogen reduction reaction (NRR) has been considered as an emerging pathway to produce ammonia (NH3) under ambient conditions owing to its low energy consumption, it still lacks efficient the electrocatalysts to dissociate inert N N bonds. Here, we develop an efficient approach to produce vanadium carbide with abundant periodic carbon vacancies (12.5 at. %) and mesoporous structure as electrocatalysts for NRR via a carbothermic reaction. The typical synthesis protocol involves the use of zinc vanadate decorated vanadium pentoxide nanosheets to homogeneously guide the nucleation and growth of metal organic frameworks (MOFs) on their surface, thus facilitating the in-situ formation of unique vanadium carbide during the subsequent carbothermic reaction. Owing to the optimized substrate-adsorbate binding strength, the intrinsic periodic carbon vacancies of the resultant vanadium carbide could act as coordinatively unsaturated sites to adsorb and activate nitrogen through π-back-donation process, thus promoting the reduction of N2 to NH3. As a consequence, a high yield rate and high Faradaic efficiency with good stabilities are achieved for producing NH3 under ambient conditions.

中文翻译：

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具有周期性阴离子空位的碳化钒可有效电催化氮还原

摘要 尽管电催化氮还原反应（NRR）因其低能耗而被认为是在环境条件下生产氨（NH3）的新兴途径，但它仍然缺乏有效的电催化剂来解离惰性的NN键。在这里，我们开发了一种有效的方法来通过碳热反应生产具有丰富的周期性碳空位（12.5at.%）和介孔结构的碳化钒作为 NRR 的电催化剂。典型的合成方案涉及使用钒酸锌装饰的五氧化二钒纳米片均匀地引导金属有机骨架 (MOF) 在其表面的成核和生长，从而促进在随后的碳热反应中原位形成独特的碳化钒。由于优化的底物-吸附物结合强度，所得碳化钒的本征周期碳空位可以作为配位不饱和位点，通过 π 回供过程吸附和活化氮，从而促进 N2 还原为 NH3。因此，在环境条件下生产 NH3 实现了高产率和高法拉第效率以及良好的稳定性。