Kong Xiangdong, Zhao Jiankang, Ke Jingwen, Wang Cheng, Li Sijia, Si Rui, Liu Bin, Zeng Jie, Geng Zhigang
Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, 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.
Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, P. R. China.
Nano Lett. 2022 May 11;22(9):3801-3808. doi: 10.1021/acs.nanolett.2c00945. Epub 2022 Apr 25.
Cu-based tandem nanocrystals have been widely applied to produce multicarbon (C) products via enhancing CO intermediate (*CO) coverage toward CO electroreduction. Nevertheless, it remains ambiguous to understand the intrinsic correlation between *CO coverage and C-C coupling. Herein, we constructed a tandem catalyst via coupling CoPc with the gas diffusion electrode of Cu (GDE of Cu-CoPc). A faradaic efficiency for C products of 82% was achieved over a GDE of Cu-CoPc at an applied current density of 480 mA cm toward CO electroreduction, which was 1.8 times as high as that over the GDE of Cu. Based on experiments and density functional theory calculations, we revealed that the high *CO coverage induced by CO-generating CoPc promoted the local enrichment of *CO with the top adsorption mode, thus reducing the energy barrier for the formation of OCCO intermediate. This work provides an in-depth understanding of the surface coverage-dependent mode-specific C-C coupling mechanism toward CO electroreduction.
铜基串联纳米晶体已被广泛应用于通过提高一氧化碳中间体（CO）覆盖率来实现一氧化碳电还原制备多碳（C）产物。然而，CO覆盖率与碳-碳偶联之间的内在关联仍不明确。在此，我们通过将钴酞菁（CoPc）与铜气体扩散电极（Cu-CoPc气体扩散电极）耦合构建了一种串联催化剂。在480 mA cm的外加电流密度下，Cu-CoPc气体扩散电极上一氧化碳电还原生成碳产物的法拉第效率达到82%，是Cu气体扩散电极的1.8倍。基于实验和密度泛函理论计算，我们揭示了由产生一氧化碳的CoPc诱导的高CO覆盖率促进了CO以顶吸附模式的局部富集，从而降低了形成OCCO中间体的能垒。这项工作为深入理解一氧化碳电还原中表面覆盖率依赖的特定模式碳-碳偶联机制提供了依据。
