Geng Qinghong, Fan Longlong, Chen Huige, Zhang Chunhui, Xu Zhe, Tian Ye, Yu Cunming, Kang Lei, Yamauchi Yusuke, Li Cuiling, Jiang Lei
School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China.
CAS Key Laboratory of Bio-Inspired Materials and Interface Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
J Am Chem Soc. 2024 Apr 17;146(15):10599-10607. doi: 10.1021/jacs.4c00082. Epub 2024 Apr 3.
The success of electrochemical CO reduction at high current densities hinges on precise interfacial transportation and the local concentration of gaseous CO. However, the creation of efficient CO transportation channels remains an unexplored frontier. In this study, we design and synthesize hydrophobic porous CuO spheres with varying pore sizes to unveil the nanoporous channel's impact on gas transfer and triple-phase interfaces. The hydrophobic channels not only facilitate rapid CO transportation but also trap compressed CO bubbles to form abundant and stable triple-phase interfaces, which are crucial for high-current-density electrocatalysis. In CO electrolysis, spectroscopy and density functional theory results reveal that atomic edges of concave surfaces promote C-C coupling an energetically favorable OC-COH pathway, leading to overwhelming CO-to-C conversion. Leveraging optimal gas transportation and active site exposure, the hydrophobic porous CuO with a 240 nm pore size (P-CuO-240) stands out among all the samples and exhibits the best CO-to-C productivity with remarkable Faradaic efficiency and formation rate up to 75.3 ± 3.1% and 2518.2 ± 8.1 μmol h cm, respectively. This study introduces a novel paradigm for efficient electrocatalysts that concurrently addresses active site design and gas-transfer challenges.
在高电流密度下电化学还原CO的成功取决于精确的界面传输和气态CO的局部浓度。然而，创建高效的CO传输通道仍是一个未被探索的前沿领域。在本研究中，我们设计并合成了具有不同孔径的疏水性多孔CuO球体，以揭示纳米多孔通道对气体传输和三相界面的影响。疏水通道不仅促进了CO的快速传输，还捕获压缩的CO气泡以形成丰富且稳定的三相界面，这对于高电流密度电催化至关重要。在CO电解中，光谱学和密度泛函理论结果表明，凹面的原子边缘促进了C-C偶联，这是一条能量有利的OC-COH途径，导致了压倒性的CO到C的转化。利用最佳的气体传输和活性位点暴露，孔径为240 nm的疏水性多孔CuO（P-CuO-240）在所有样品中脱颖而出，表现出最佳的CO到C的生产率，具有显著的法拉第效率，形成速率分别高达75.3±3.1%和2518.2±8.1 μmol h cm。本研究引入了一种新型高效电催化剂范例，同时解决了活性位点设计和气体传输挑战。
