Yang Peng-Peng, Zhang Xiao-Long, Gao Fei-Yue, Zheng Ya-Rong, Niu Zhuang-Zhuang, Yu Xingxing, Liu Ren, Wu Zhi-Zheng, Qin Shuai, Chi Li-Ping, Duan Yu, Ma Tao, Zheng Xu-Sheng, Zhu Jun-Fa, Wang Hui-Juan, Gao Min-Rui, Yu Shu-Hong
Division of Nanomaterials & Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, CAS Center for Excellence in Nanoscience, Hefei Science Center of CAS, Collaborative Innovation Center of Suzhou Nano Science and Technology, Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China.
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, P. R. China.
J Am Chem Soc. 2020 Apr 1;142(13):6400-6408. doi: 10.1021/jacs.0c01699. Epub 2020 Mar 23.
Selective and efficient catalytic conversion of carbon dioxide (CO) into value-added fuels and feedstocks provides an ideal avenue to high-density renewable energy storage. An impediment to enabling deep CO reduction to oxygenates and hydrocarbons (e.g., C compounds) is the difficulty of coupling carbon-carbon bonds efficiently. Copper in the +1 oxidation state has been thought to be active for catalyzing C formation, whereas it is prone to being reduced to Cu at cathodic potentials. Here we report that catalysts with nanocavities can confine carbon intermediates formed , which in turn covers the local catalyst surface and thereby stabilizes Cu species. Experimental measurements on multihollow cuprous oxide catalyst exhibit a C Faradaic efficiency of 75.2 ± 2.7% at a C partial current density of 267 ± 13 mA cm and a large C-to-C ratio of ∼7.2. Operando Raman spectra, in conjunction with X-ray absorption studies, confirm that Cu species in the as-designed catalyst are well retained during CO reduction, which leads to the marked C selectivity at a large conversion rate.
将二氧化碳（CO₂）选择性且高效地催化转化为增值燃料和原料，为高密度可再生能源存储提供了一条理想途径。实现将CO₂深度还原为含氧化合物和碳氢化合物（如C₁化合物）的一个障碍是难以有效地耦合碳-碳键。氧化态为+1的铜被认为对催化C-C键形成具有活性，然而在阴极电位下它易于被还原为金属铜。在此我们报道，具有纳米腔的催化剂能够限制所形成的碳中间体，这反过来覆盖了局部催化剂表面，从而稳定了铜物种。对多中空氧化亚铜催化剂的实验测量表明，在C₂H₄分电流密度为267±13 mA cm⁻²时，C₂H₄的法拉第效率为75.2±2.7%，且C₂H₄与C₂H₆的比例高达约7.2。原位拉曼光谱结合X射线吸收研究证实，在设计的催化剂中，铜物种在CO₂还原过程中得到了很好的保留，这导致在高转化率下具有显著的C₂H₄选择性。
