Engineering Hydrogen Generation Sites to Promote Electrocatalytic CO 2 Reduction to Formate

作者：Xinyue Guo, Simin Xu, Hua Zhou, Yue Ren, Ruixiang Ge, Ming Xu, Lirong Zheng, Xianggui Kong, Mingfei Shao, Zhenhua Li, Haohong Duan · 发表于：ACS Catalysis · 年份：2022 · DOI：10.1021/acscatal.2c02548 · 被引用次数：96 · 研究领域：CO2 Reduction Techniques and Catalysts、Ionic liquids properties and applications、Advanced Photocatalysis Techniques

Electrocatalytic reduction of carbon dioxide (CO 2 ER) to produce formate is an economically viable route for CO 2 upgrading. Bismuth (Bi)-based materials have been recognized as promising catalysts for this reaction but suffer from low activity that hinders their practical applications. Here, we report a cooperative catalyst of silver nanoparticles (Ag NPs) supported on a layered bismuth subcarbonate (Bi 2 O 2 CO 3; BOC) nanosheet array (Ag/BOC), which achieves a 2-fold higher reaction rate in comparison to pure BOC with a high Faradaic efficiency (FE) of 98% to formate, and the FE is maintained at >85% over a wide potential window from −0.86 to −1.26 V vs RHE. Experimental results combined with theoretical results reveal that Ag accelerates the dissociation of H 2 O to supply reactive hydrogen species, which migrate to adjacent Bi sites to accomplish CO 2 reduction with promoted activity. Moreover, we realized coproduction of formate at two poles of a homemade two-electrode flow cell by pairing the CO 2 ER (at the cathode) and electrooxidation of glycerol (at the anode), achieving an apparent formate FE of 130% at 2.2 V, as well as a 63% electric energy saving for formate production in comparison with the traditional CO 2 ER coupled with the water oxidation reaction.