College of Chemical and Biological Engineering, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Zhejiang University, 310027 Hangzhou, P. R. China.
Institute of Zhejiang University Quzhou, Zheda Road #99, 324000 Quzhou, P. R. China.
ACS Appl Mater Interfaces. 2023 Jun 21;15(24):29244-29251. doi: 10.1021/acsami.3c06739. Epub 2023 Jun 8.
Renewable energy-driven, electrocatalytic nitrogen reduction reaction (NRR) is a promising strategy for ammonia synthesis. However, improving catalyst activity and selectivity under ambient conditions has long been challenging. In this work, we obtained the potential active V-N center through theoretical prediction and successfully constructed the associated V-N/N structure on N-doped carbon materials. Surprisingly, such a catalyst exhibits excellent electrocatalytic NRR performance. The V-N catalyst affords a remarkably high faradaic efficiency of 76.53% and an NH yield rate of 31.41 μg h mg at -0.3 V vs RHE. The structural characterization and density functional theory (DFT) calculations verified that the high performance of the catalyst originates from the tuned d-band upon coordination with nitrogen, in line with the original design intention as derived theoretically. Indeed, the V-N center with carbon defects enhances dinitrogen adsorption and charge transfer, thereby lowering the energy barriers to form the *NNH intermediates. Such a strategy as a rational design─controllable synthesis─theoretical verification may prove effective as well for other chemical processes.
可再生能源驱动的电催化氮气还原反应（NRR）是合成氨的一种很有前途的策略。然而，在环境条件下提高催化剂的活性和选择性一直是一个挑战。在这项工作中，我们通过理论预测得到了潜在的活性 V-N 中心，并成功地在氮掺杂碳材料上构建了相关的 V-N/N 结构。令人惊讶的是，这种催化剂表现出了优异的电催化 NRR 性能。V-N 催化剂在 -0.3 V 相对于 RHE 的电位下，表现出了高达 76.53%的法拉第效率和 31.41μg h mg 的 NH 生成速率。结构表征和密度泛函理论（DFT）计算证实，催化剂的高性能源于与氮配位时 d 带的调谐，与理论上的原始设计意图一致。实际上，具有碳缺陷的 V-N 中心增强了二氮的吸附和电荷转移，从而降低了形成*NNH 中间体的能垒。这种策略作为一种合理的设计——可控合成——理论验证，对于其他化学过程可能同样有效。
