Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States.
State Key Laboratory of Applied Organic Chemistry, Frontiers Science Center for Rare Isotopes, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
J Am Chem Soc. 2021 Sep 22;143(37):15335-15343. doi: 10.1021/jacs.1c06877. Epub 2021 Sep 14.
We report a new form of catalyst based on ferromagnetic hexagonal-close-packed (hcp) Co nanosheets (NSs) for selective CORR to ethanal, CHCHO. In all reduction potentials tested from -0.2 to -1.0 V (vs RHE) in 0.5 M KHCO solution, the reduction yields ethanal as a major product and ethanol/methanol as minor products. At -0.4 V, the Faradaic efficiency (FE) for ethanal reaches 60% with current densities of 5.1 mA cm and mass activity of 3.4 A g (total FE for ethanal/ethanol/methanol is 82%). Density functional theory (DFT) calculations suggest that this high CORR selectivity to ethanal on the hcp Co surface is attributed to the unique intralayer electron transfer, which not only promotes [OC-CO]* coupling but also suppresses the complete hydrogenation of the coupling intermediates to ethylene, leading to highly selective formation of CHCHO.
我们报告了一种基于铁磁六方密排（hcp）Co 纳米片（NSs）的新型催化剂，用于选择性 CORR 生成乙醛，CHCHO。在 0.5 M KHCO3 溶液中，在 -0.2 至-1.0 V（相对于 RHE）的所有测试还原电位下，还原产物主要为乙醛，乙醇/甲醇为次要产物。在-0.4 V 时，乙醛的法拉第效率（FE）达到 60%，电流密度为 5.1 mA cm，质量活度为 3.4 A g（总 FE 为乙醛/乙醇/甲醇为 82%）。密度泛函理论（DFT）计算表明，hcp Co 表面上这种高 CORR 对乙醛的高选择性归因于独特的层内电子转移，这不仅促进了[OC-CO]*偶联，而且抑制了偶联中间体的完全氢化生成乙烯，从而导致 CHCHO 的高选择性形成。
