Wu Weixing, Wang Ying
Department of Chemistry, The Chinese University of Hong Kong, New Territories, Hong Kong S. A. R., China.
J Am Chem Soc. 2025 Apr 9;147(14):11662-11666. doi: 10.1021/jacs.5c01149. Epub 2025 Mar 31.
Carbonate formation constitutes a major obstacle in the electrochemical CO reduction reaction (CORR), restricting the industrial implementation of this reaction. Even when adopting mild acidic electrolytes, carbonate formation is still observed. The fundamental reason lies in the inevitable OH generation when HO is the proton donor, leading to subsequent carbonate formation. Thus, exploring the reaction pathway of the CORR in the acid, especially if a proton can directly participate in the reaction, is critical. Herein, we employed a rotating ring-disk electrode and surface interrogation scanning electrochemical microscopy to investigate the electrode process of the CORR in acid. A pH-dependent behavior of CORR is observed, indicating proton acting as the reactant in the RDS, originating from the early onset of CO adsorption under locally acidic conditions.
碳酸盐的形成是电化学CO还原反应（CORR）中的一个主要障碍，限制了该反应的工业应用。即使采用温和的酸性电解质，仍会观察到碳酸盐的形成。根本原因在于当HO作为质子供体时不可避免地会产生OH，从而导致随后碳酸盐的形成。因此，探索CORR在酸性条件下的反应途径，特别是质子是否能直接参与反应，至关重要。在此，我们采用旋转环盘电极和表面询问扫描电化学显微镜来研究CORR在酸性条件下的电极过程。观察到CORR的pH依赖性行为，表明质子在速率决定步骤中作为反应物，这源于局部酸性条件下CO吸附的早期开始。
