Wang Xinkai, Yang Yang, Zhang Xian-Ming
Key Laboratory of Interface Science and Engineering in Advanced Material (Ministry of Education), College of Chemistry & Chemical Engineering, Taiyuan University of Technology, Taiyuan, 030024, P. R. China.
College of Materials Science and Engineering, Qiqihar University, Qiqihar, Heilongjiang, 161006, P. R. China.
Dalton Trans. 2025 Aug 5;54(31):11977-11984. doi: 10.1039/d5dt01169h.
Understanding the structural changes of high-performance CO-to-CH catalysts and determining the mode of C-C coupling at active sites during the electrochemical CO reduction reaction (ECORR) are crucial. Molecular catalysts with readily identifiable and uniform active sites permit the elucidation of reaction mechanisms at the molecular level, serving as an optimal platform for investigating the ECORR. Here we report the dynamic structural reconfiguration of a mixed-valence copper-based complex ([CuCl(phen)][CuCl]; phen = 1,10-phenanthroline) during the ECORR and elucidate the mechanism for its enhanced selectivity towards CH. The [CuCl(phen)][CuCl] catalyst exhibits outstanding performance with a maximum faradaic efficiency for CH of 47% at -1.2 V RHE. The excellent performance is maintained for at least 4.5 h. During the ECORR, the Cu(II) in the [CuCl(phen)] unit is reduced to Cu(I) and the chlorine atom dissociates at high potential to form an exposed Cu(I) site, possibly resulting in cuprophilic interactions between the two Cu sites. The reconstruction shortens the Cu-Cu distance in the [CuCl(phen)][CuCl] complex, facilitating the dimerization of *CO and *CHO intermediates to produce CH. This work presents a fresh perspective on designing ECORR catalysts to produce multi-carbon products through an reconfiguration process.
了解高性能CO转化为CH催化剂的结构变化，并确定电化学CO还原反应（ECORR）过程中活性位点处的C-C偶联模式至关重要。具有易于识别且均匀的活性位点的分子催化剂能够在分子水平上阐明反应机理，是研究ECORR的理想平台。在此，我们报道了一种混合价态铜基配合物（[CuCl(phen)][CuCl]；phen = 1,10-菲咯啉）在ECORR过程中的动态结构重构，并阐明了其对CH选择性增强的机理。[CuCl(phen)][CuCl]催化剂表现出优异的性能，在-1.2 V RHE下对CH的最大法拉第效率为47%。这种优异性能至少保持4.5小时。在ECORR过程中，[CuCl(phen)]单元中的Cu(II)还原为Cu(I)，氯原子在高电位下解离形成暴露的Cu(I)位点，这可能导致两个Cu位点之间形成亲铜相互作用。这种重构缩短了[CuCl(phen)][CuCl]配合物中的Cu-Cu距离，促进了CO和CHO中间体的二聚化以生成CH。这项工作为通过重构过程设计用于生产多碳产物的ECORR催化剂提供了新的视角。
