催化学报

催化学报 ›› 2026, Vol. 81: 206-215.DOI: 10.1016/S1872-2067(25)64886-8

• 论文 • 上一篇    下一篇

咪唑阳离子调控银电极界面促进电化学CO2还原作用的研究

宋殿坤a,1, 吴云云b,1, 华家辉a,1, 邵春风a(), 魏朝阳b(), 王键吉c(), 代凯a()   

  1. a 淮北师范大学化学与化工学院, 能源科学与工程学院, 绿色和精准合成化学及应用教育部重点实验室, 安徽污染物敏感材料与环境修复重点实验室, 安徽淮北 235000
    b 湖北大学材料科学与工程学院, 有机化工新材料湖北省协同创新中心, 功能材料绿色制备与应用教育部重点实验室, 高分子材料湖北省重点实验室, 湖北武汉 430062
    c 河南师范大学化学化工学院, 绿色化学介质与反应教育部重点实验室, 精细化学品绿色制造河南省协同创新中心, 河南新乡 453007
  • 收稿日期:2025-07-05 接受日期:2025-09-16 出版日期:2026-02-18 发布日期:2025-12-26
  • 通讯作者: *电子信箱: shaocf@chnu.edu.cn (邵春风),weizy@hubu.edu.cn (魏朝阳),jwang@htu.edu.cn (王键吉),daikai940@chnu.edu.cn (代凯).
  • 作者简介:1共同第一作者.
  • 基金资助:
    国家自然科学基金委员会(22578154);国家自然科学基金委员会(22278169);国家自然科学基金委员会(22508135);安徽省教育厅优秀科研创新团队计划(2022AH010028);安徽省教育厅重点项目(2022AH050376)

Insight into the role of imidazolium cations in regulating Ag electrode interface for enhancing electrochemical CO2 reduction

Diankun Songa,1, Yunyun Wub,1, Jiahui Huaa,1, Chunfeng Shaoa(), Zhaoyang Weib(), Jianji Wangc(), Kai Daia()   

  1. a Key Laboratory of Green and Precise Synthetic Chemistry and Applications, Ministry of Education, Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation, School of Chemistry and Chemical Engineering, School of Energy Science and Engineering, Huaibei Normal University, Huaibei 235000, Anhui, China
    b Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Key Laboratory of Polymer Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062, Hubei, China
    c Key Laboratory of Green Chemical Media and Reactions (Ministry of Education), Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang 453007, Henan, China
  • Received:2025-07-05 Accepted:2025-09-16 Online:2026-02-18 Published:2025-12-26
  • Contact: *E-mail: shaocf@chnu.edu.cn (C. Shao),weizy@hubu.edu.cn (Z. Wei),jwang@htu.edu.cn (J. Wang),daikai940@chnu.edu.cn (K. Dai).
  • About author:1 Contributed equally to this work.
  • Supported by:
    National Natural Science Foundation of China(22578154);National Natural Science Foundation of China(22278169);National Natural Science Foundation of China(22508135);Excellent Scientific Research and Innovation Team Program of the Education Department of Anhui Province(2022AH010028);Key Foundation of the Educational Commission of Anhui Province(2022AH050376)

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摘要：

CO2电化学还原反应(CO2RR)是减少碳排放与实现碳循环的关键技术, 但其工业应用受催化剂失活和析氢(HER)副反应制约. 作为界面反应, CO2RR性能不仅取决于催化剂活性, 更受电极/电解质界面局部物理化学区域影响. 离子液体(ILs)因高CO2溶解度、强活化能力及宽电化学窗口, 成为理想电解质. 研究表明, ILs中的咪唑阳离子结构与界面催化行为存在强构效关系: 咪唑阳离子在电极界面的分布、咪唑环取代基位置及烷基链长度均影响催化动力学. 然而, 目前阳离子结构对反应动力学的调控机制, 尤其是烷基链长(CACL)在调节界面局部物理化学区域结构及CO2吸附输运中的作用仍不明确, 亟待深入研究.

本研究系统阐明了咪唑类ILs阳离子结构对银电极界面的动态调控机制及其在电化学CO2RR中的作用. 通过精准调控咪唑基离子液体阳离子的烷基链长度, 证实此类阳离子可有效调节电极界面的电双层结构: 原位衰减全反射表面增强红外光谱与分子动力学模拟结果表明, 垂直排列的长烷基链在电极表面形成疏水层, 显著增强CO2的质量传输与局部富集; 水平取向的咪唑环则通过稳定CO2还原关键中间体, 降低反应活化能垒, 同步抑制HER. 密度泛函理论计算结果表明, 临界链长的咪唑阳离子较长短链同系物具有更低的CO2传输能垒, 优化了界面CO2的可及性. 数密度分布和均方位移进一步证实了上述结果, 突出了阳离子排列在电极/电解质界面的关键作用. 五种不同烷基链长的ILs电解质体系中的电化学测试证实, 含中等链长阳离子的电解质展现出最优催化性能: 商用银电极在较宽的电位区间内实现极高的CO法拉第效率, 维持高电流密度且具备良好的长期稳定性. 这种具有临界链长咪唑阳离子的电解质显著地平衡了一系列正负因素, 包括疏水性、CO2吸收、电导率、粘度和HER等. 这些效应共同协同塑造了一个优化的界面局部物理化学区域, 提高了CO2催化反应的速率. 跨尺度表征还发现, 该调控机制在Cu, Ni等多种金属电极体系中具有普适性, 揭示了CACL通过优化界面双电层结构与反应动力学提升催化性能的本质规律. 这些效应协同塑造了一个优化的物理化学界面, 提高了CO2催化反应的速率. 跨尺度表征还发现, 该调控机制在Cu,Ni等多种金属电极体系中具有普适性, 揭示了CACL通过优化界面双电层结构与反应动力学提升催化性能的本质规律.

未来CO2RR领域需攻克ILs高成本、难回收及粘高导低等规模化瓶颈, 推动技术落地. 本文揭示ILs阳离子界面调控机制, 为优化ILs结构、平衡性能与成本及设计适配催化体系提供关键依据, 助力突破规模化障碍.

关键词: 离子液体, 阳离子烷基链长度, CO2还原反应, 分子动力学模拟, 电解质

Abstract:

Imidazolium-based ionic liquids (ILs) exhibit great potential in promoting electrochemical CO2 reduction reaction (CO2RR) by reducing overpotential reduction and enhancing catalytic efficiency. However, the regulatory role of ILs structure in the local physicochemical region at the electrode/electrolyte interface and in reaction kinetics remain unclear. In this study, we designed imidazolium-based ILs with tunable cation alkyl chain length and systematically revealed the dynamic interfacial regulation mechanism controlled by cation structure, based on in-situ infrared spectroscopy and molecular dynamics simulations. The commercial Ag electrodes in electrolytes with critical chain length exhibit nearly 100% Faradaic efficiency for CO production while maintaining high current density. Imidazolium cations with critical chain length effectively regulate the electric double layer at the Ag electrode/electrolyte interface: they notably balance a range of positive and negative factors, including hydrophobicity, CO2 absorption, conductivity, viscosity, and hydrogen evolution reaction, etc. Collectively, these effects synergistically shape an optimized interfacial local physicochemical region, enhancing the rate of CO2 catalytic reactions. This work elucidates the mechanistic framework of interfacial regulation in CO2RR and delivers molecular design principles for engineering IL-based electrolytes toward enhanced catalytic selectivity.

Key words: Ionic liquids, Cation alkyl chain length, CO2 reduction reaction, Molecular dynamics simulations, Electrolyte