Kou Meimei, Yuan Ying, Zhao Ruili, Wang Youkui, Zhao Jiamin, Yuan Qing, Zhao Jinsheng
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Molecules. 2024 May 11;29(10):2261. doi: 10.3390/molecules29102261.
The insight of the activity phase and reaction mechanism is vital for developing high-performance ammonia synthesis electrocatalysts. In this study, the origin of the electronic-dependent activity for the model CuO catalyst toward ammonia electrosynthesis with nitrate was probed. The modulation of the electronic state and oxygen vacancy content of CuO was realized by doping with halogen elements (Cl, Br, I). The electrocatalytic experiments showed that the activity of the ammonia production depends strongly on the electronic states in CuO. With increased electronic state defects in CuO, the ammonia synthesis performance increased first and then decreased. The CuO/Br with electronic defects in the middle showed the highest ammonia yield of 11.4 g h g at -1.0 V (vs. RHE), indicating that the pattern of change in optimal ammonia activity is consistent with the phenomenon of volcano curves in reaction chemistry. This work highlights a promising route for designing NORR to NH catalysts.
了解活性阶段和反应机理对于开发高性能氨合成电催化剂至关重要。在本研究中，探究了模型CuO催化剂对硝酸盐氨电合成的电子依赖性活性的起源。通过掺杂卤素元素（Cl、Br、I）实现了CuO电子态和氧空位含量的调控。电催化实验表明，氨生成活性强烈依赖于CuO中的电子态。随着CuO中电子态缺陷的增加，氨合成性能先增加后降低。具有中等电子缺陷的CuO/Br在-1.0 V（相对于可逆氢电极）下显示出最高氨产率为11.4 g h g，表明最佳氨活性的变化模式与反应化学中的火山曲线现象一致。这项工作突出了一条设计用于将硝酸盐电还原为氨的催化剂的有前景的途径。
