CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, CAS Research/Education Center for Excellence in Molecular Sciences, Beijing National Laboratory for Molecular Science (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing100190, China.
University of Chinese Academy of Sciences, Beijing100049, China.
J Am Chem Soc. 2022 Nov 2;144(43):20126-20133. doi: 10.1021/jacs.2c09862. Epub 2022 Oct 19.
We report herein the electrochemical scanning tunneling microscopy (ECSTM) study on the synergistic effect of Mg in CO reduction reaction (CORR) catalyzed by cobalt phthalocyanine (CoPc). ECSTM measurement molecularly resolves the self-assembled CoPc monolayer on the Au(111) substrate. In the CO environment, high-contrast species are observed in the adlayer and assigned to the CO adsorption on CoPc. Furthermore, the contrast of the CO-bound complex is higher in Mg-containing electrolytes than in Mg-free electrolytes, indicating the formation of the CoPc-CO-Mg complex. The surface coverage of adsorbed CO is positively correlated with the Mg concentration as the additive in electrolytes up to a plateau of 30.8 ± 2.7% when (Mg) > 30 mM. The potential step experiment indicates the higher CO adsorption dynamics in Mg-containing electrolytes than without Mg. The rate constants of CO adsorption and dissociation in different electrolytes are extracted from the data fitting of statistical results from ECSTM experiments.
我们在此报告了电化学扫描隧道显微镜（ECSTM）在镁协同钴酞菁（CoPc）催化一氧化碳还原反应（CORR）中的研究。ECSTM 测量分子解析了在 Au(111) 衬底上自组装的 CoPc 单层。在 CO 环境中，在吸附层中观察到高对比度的物种，并将其分配给 CoPc 上的 CO 吸附。此外，在含有镁的电解液中，与不含镁的电解液相比，CO 结合复合物的对比度更高，表明形成了 CoPc-CO-Mg 配合物。吸附 CO 的表面覆盖率与镁浓度呈正相关，当 (Mg) > 30 mM 时，在电解质中的添加剂达到 30.8 ± 2.7%的平台。电位阶跃实验表明，在含有镁的电解液中 CO 的吸附动力学更高。从 ECSTM 实验的统计结果拟合中提取了不同电解液中 CO 吸附和离解的速率常数。
