State Key Lab of Organic-Inorganic Composites, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.
Institute of Chemistry Chinese Academy of Sciences, Beijing, 100029, P. R. China.
Angew Chem Int Ed Engl. 2023 Jul 17;62(29):e202303794. doi: 10.1002/anie.202303794. Epub 2023 Jun 13.
Electrocatalytic nitrogen reduction reaction (ENRR) has emerged as a promising approach to synthesizing green ammonia under ambient conditions. Tungsten (W) is one of the most effective ENRR catalysts. In this reaction, the protonation of intermediates is the rate-determining step (RDS). Enhancing the adsorption of intermediates is crucial to increase the protonation of intermediates, which can lead to improved catalytic performance. Herein, we constructed a strong interfacial electric field in WS -WO to elevate the d-band center of W, thereby strengthening the adsorption of intermediates. Experimental results demonstrated that this approach led to a significantly improved ENRR performance. Specifically, WS -WO exhibited a high NH yield of 62.38 μg h mg and a promoted faraday efficiency (FE) of 24.24 %. Furthermore, in situ characterizations and theoretical calculations showed that the strong interfacial electric field in WS -WO upshifted the d-band center of W towards the Fermi level, leading to enhanced adsorption of -NH and -NH intermediates on the catalyst surface. This resulted in a significantly promoted reaction rate of the RDS. Overall, our study offers new insights into the relationship between interfacial electric field and d-band center and provides a promising strategy to enhance the intermediates adsorption during the ENRR process.
电催化氮气还原反应 (ENRR) 已成为在环境条件下合成绿色氨的一种很有前途的方法。钨 (W) 是最有效的 ENRR 催化剂之一。在该反应中，中间体的质子化是决速步骤 (RDS)。增强中间体的吸附能力对于增加中间体的质子化至关重要，这可以提高催化性能。在此，我们在 WS -WO 中构建了一个强的界面电场，以提高 W 的 d 带中心，从而增强中间体的吸附能力。实验结果表明，这种方法显著提高了 ENRR 的性能。具体而言，WS -WO 表现出 62.38μg h mg 的高 NH 产量和 24.24%的增强法拉第效率 (FE)。此外，原位表征和理论计算表明，WS -WO 中的强界面电场将 W 的 d 带中心向上移动到费米能级，导致催化剂表面上 -NH 和 -NH 中间体的吸附增强。这导致 RDS 的反应速率显著提高。总的来说，我们的研究提供了关于界面电场和 d 带中心之间关系的新见解，并为增强 ENRR 过程中的中间体吸附提供了一种有前途的策略。
