Tensile‐Strained Cu Penetration Electrode Boosts Asymmetric C−C Coupling for Ampere‐Level CO<sub>2</sub>‐to‐C<sub>2+</sub> Reduction in Acid
Shoujie Li, Gangfeng Wu, Jianing Mao, Aohui Chen, Xiaohu Liu, Jianrong Zeng, Yiheng Wei, Jiangjiang Wang, Huanyi Zhu, Jiayu Xia, Xiaotong Wang, Guihua Li, Yanfang Song, Xiao Dong, Wei Wei, Wei Chen
Abstract
Abstract The synthesis of multicarbon (C 2+ ) products remains a substantial challenge in sustainable CO 2 electroreduction owing to the need for sufficient current density and faradaic efficiency alongside carbon efficiency. Herein, we demonstrate ampere‐level high‐efficiency CO 2 electroreduction to C 2+ products in both neutral and strongly acidic (pH=1) electrolytes using a hierarchical Cu hollow‐fiber penetration electrode (HPE). High concentration of K + could concurrently suppress hydrogen evolution reaction and facilitate C−C coupling, thereby promoting C 2+ production in strong acid. By optimizing the K + and H + concentration and CO 2 flow rate, a faradaic efficiency of 84.5 % and a partial current density as high as 3.1 A cm −2 for C 2+ products, alongside a single‐pass carbon efficiency of 81.5 % and stable electrolysis for 240 h were demonstrated in a strong acidic solution of H 2 SO 4 and KCl (pH=1). Experimental measurements and density functional theory simulations suggested that tensile‐strained Cu HPE enhances the asymmetric C−C coupling to steer the selectivity and activity of C 2+ products.