Controlling the Phase Composition of Pre‐Catalysts to Obtain Abundant Cu(111)/Cu(200) Grain Boundaries for Enhancing Electrocatalytic CO 2 Reduction Selectivity to Ethylene

作者：Zekun Zhang, Shiji Li, Qian Zhang, Mingtao Li, Yang Liu, Wei Yan, Hao Xu · 发表于：Small · 年份：2024 · DOI：10.1002/smll.202409001 · 被引用次数：16 · 研究领域：CO2 Reduction Techniques and Catalysts、Ionic liquids properties and applications、Carbon dioxide utilization in catalysis

Abstract The preparation of ethylene (C 2 H 4 ) by electrochemical CO 2 reduction (ECO 2 R) has dramatically progressed in recent years. However, the slow kinetics of carbon‐carbon (C‐C) coupling remains a significant challenge. A generalized facet reconstruction strategy is reported to prepare a 3‐phase mixed pre‐catalyst (Cu 3 N‐300) of Cu 3 N, Cu 2 O, and CuO by controlling the calcination temperature and to obtain the derived Cu catalyst (A‐Cu 3 N‐300‐0.5) enriched with Cu(111)/Cu(200) grain boundaries (GBs) by subsequent constant potential reduction. Its Faraday efficiency (FE) toward C 2 H 4 at a low reaction potential of −1.07 V (vs reversible hydrogen electrode (RHE)) is 46.03%, which is much higher than the other 3 derived Cu catalysts containing single Cu(111) facets (24.89% and 24.52%) and Cu(111)/Cu(111) GBs (28.66%). Combining in situ experimental and theoretical computational studies, abundant Cu(111)/Cu(200) GBs is found to enhance CO 2 activation and significantly promote the formation and adsorption of *CO intermediates, thereby lowering the activation energy barrier of C‐C coupling and increasing the FE of C 2 H 4 .