Wu Yuheng, Kong Xiangdong, Su Yechao, Zhao Jiankang, Ma Yiling, Ji Tongzheng, Wu Di, Meng Junyang, Liu Yan, Geng Zhigang, Zeng Jie
Hefei National Research Center for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China.
School of Chemistry & Chemical Engineering, Anhui University of Technology, Ma'anshan, Anhui 243002, P. R. China.
Precis Chem. 2024 Feb 15;2(3):112-119. doi: 10.1021/prechem.3c00107. eCollection 2024 Mar 25.
Electroreduction of nitrate (NO ) to ammonia (NH) is an environmentally friendly route for NH production, serving as an appealing alternative to the Haber-Bosch process. Recently, various noble metal-based electrocatalysts have been reported for electroreduction of NO . However, the application of pure metal electrocatalysts is still limited by unsatisfactory performance, owing to the weak adsorption of nitrogen-containing intermediates on the surface of pure metal electrocatalysts. In this work, we report thiol ligand-modified Au nanoparticles as the effective electrocatalysts toward electroreduction of NO . Specifically, three mercaptobenzoic acid (MBA) isomers, thiosalicylic acid (ortho-MBA), 3-mercaptobenzoic acid (meta-MBA), and 4-mercaptobenzoic acid (para-MBA), were employed to modify the surface of the Au nanocatalyst. During the NO electroreduction, para-MBA modified Au (denoted as para-Au/C) displayed the highest catalytic activity among these Au-based catalysts. At -1.0 V versus reversible hydrogen electrode (vs RHE), para-Au/C exhibited a partial current density for NH of 472.2 mA cm, which was 1.7 times that of the pristine Au catalyst. Meanwhile, the Faradaic efficiency (FE) for NH reached 98.7% at -1.0 V vs RHE for para-Au/C. The modification of para-MBA significantly improved the intrinsic activity of the Au/C catalyst, thus accelerating the kinetics of NO reduction and giving rise to a high NH yield rate of para-Au/C.
将硝酸盐（NO₃⁻）电还原为氨（NH₃）是一种生产NH₃的环境友好型途径，是哈伯-博施法颇具吸引力的替代方法。最近，已有多种基于贵金属的电催化剂被报道用于NO₃⁻的电还原。然而，由于含氮中间体在纯金属电催化剂表面的吸附较弱，纯金属电催化剂的应用仍受限于其不尽人意的性能。在本工作中，我们报道了硫醇配体修饰的金纳米颗粒作为NO₃⁻电还原的有效电催化剂。具体而言，三种巯基苯甲酸（MBA）异构体，即硫代水杨酸（邻位-MBA）、3-巯基苯甲酸（间位-MBA）和4-巯基苯甲酸（对位-MBA）被用于修饰金纳米催化剂的表面。在NO₃⁻电还原过程中，对位-MBA修饰的金（记为对位-Au/C）在这些基于金的催化剂中表现出最高的催化活性。相对于可逆氢电极（vs RHE）在-1.0 V时，对位-Au/C的NH₃分电流密度为472.2 mA cm⁻²，是原始金催化剂的1.7倍。同时，对于对位-Au/C，相对于RHE在-1.0 V时NH₃的法拉第效率（FE）达到98.7%。对位-MBA的修饰显著提高了Au/C催化剂的本征活性，从而加速了NO₃⁻还原的动力学，并使对位-Au/C的NH₃产率较高。
