Constructing a Localized Buffer Interlayer to Elevate High-Rate CO<sub>2</sub>-to-C<sub>2+</sub> Electrosynthesis
Guobin Wen, Bohua Ren, Xin Wang, Lichao Tan, Silong Dong, Haoyang Xiong, Rui Gao, Dan Luo, Xiaoman Duan, Ning Zhu, Qianyi Ma, Aiping Yu, Zhongwei Chen
Abstract
Catalytic surface and interface engineering for the electrosynthesis of multicarbon chemicals from CO 2 are widely investigated, while the selective regulation of mass transport for reactant CO 2 and intermediate CO remains rarely explored, which is a critical challenge limiting the C 2+ production rate. Here, we strategically construct a buffer interlayer with soluble ionic liquid (IL) additives between the aqueous electrolyte and the catalytic surface, which not only regulates the microenvironment of CO and CO 2 at different reaction stages but also stabilizes catalytic sites. The CO residence time is extended in the buffer interlayer ascribed to the attractive interactions via dipole–dipole interactions and hydrogen bonding. CO 2 and its transport are enhanced by the buffer reactions in the aqueous interlayer within the flow-through compact cell. Meanwhile, the utilization of ILs stabilizes active sites (Cu 2 O-derived Cu) by facilitating the regeneration of Cu 2 O through the applied potentials. Consequently, C 2+ products are synthesized at a high rate with a partial current density of 1.30 A/cm 2 for over 200 h. This concept is further scaled to a 100 cm 2 flow cell, exhibiting a carbon loss below 6%. Such a systematic investigation establishes a general construction strategy for the buffer interlayer and catalytic sites in electrolysis.