催化学报 ›› 2022, Vol. 43 ›› Issue (11): 2772-2791.DOI: 10.1016/S1872-2067(22)64095-6

• 综述 • 上一篇    下一篇

CO2电还原反应中的基础问题及原位振动光谱的对策

李宏a, 蒋昆b, 邹受忠c,#(), 蔡文斌a,*()   

  1. a复旦大学化学系, 能源材料化学协同创新中心, 上海市分子催化与功能材料表面重点实验室, 上海 200438, 中国
    b上海交通大学机械与动力工程学院, 上海 200240, 中国
    c美利坚大学化学系, 华盛顿, 美国
  • 收稿日期:2022-04-30 接受日期:2022-07-27 出版日期:2022-11-18 发布日期:2022-10-20
  • 通讯作者: 邹受忠,蔡文斌
  • 基金资助:
    国家自然科学基金(21733004);国家自然科学基金(22002088);上海市“科技创新行动计划”政府间国际科技合作基金项目(17520711200);上海市青年科技英才扬帆计划(20YF1420500)

Fundamental aspects in CO2 electroreduction reaction and solutions from in situ vibrational spectroscopies

Hong Lia, Kun Jiangb, Shou-Zhong Zouc,#(), Wen-Bin Caia,*()   

  1. aShanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, Fudan University, Shanghai 200438, China
    bSchool of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
    cDepartment of Chemistry, American University, Washington, District of Columbia 20016, United States
  • Received:2022-04-30 Accepted:2022-07-27 Online:2022-11-18 Published:2022-10-20
  • Contact: Shou-Zhong Zou, Wen-Bin Cai
  • About author:Shouzhong Zou (Department of Chemistry, American University) earned his B.S. in Chemistry in 1991 and completed his MS studies in 1994 from Xiamen University under the guidance of Prof. Zhong-Qun Tian. He received his Ph.D. in Chemistry from Purdue University in 1999 under the direction of Prof. Michael J. Weaver. He then did postdoctoral work at Caltech with Profs. Fred C Anson and Ahmed H. Zewail. He started his independent research as an assistant professor in 2002 at Miami University (Oxford, Ohio), and was promoted to associate professor in 2008. He joined American University in the summer of 2015 as a full professor and chair. His research interests include developing catalysts for low temperature fuel cells, CO2 reduction and gas sensing, and advancing spectroscopic and microscopic techniques for the characterization of surfaces and interfaces.
    Wen-Bin Cai (Department of Chemistry, Fudan University) received his B.A. degree and M.S. degree from Shanghai University of Science and Technology in 1989 and 1992, respectively, under the guidance of Prof. Xun-Nan Deng and Ph.D. degree from Fudan University in 1995 under the guidance of Prof. Wei-Fang Zhou. From 1995 to 2002, he did postdoctoral research work consecutively at Xiamen University (with Prof. Zhong-Qun Tian), Hokkaido University (with Prof. Masatoshi Osawa), and Case Western Reserve University (with Profs. Daniel Scherson and James Burgess). Since July 2002, he has been a professor at Fudan University. His research interests cover interfacial spectroelectrochemistry and electrocatalysis, including but not limited to methodological development and application of electrochemical ATR-SEIRAS, mechanistic understanding and catalyst development towards electrocatalysis of small organic molecule oxidation, oxygen reduction and carbon dioxide reduction.
  • Supported by:
    National Natural Science Foundation of China(21733004);National Natural Science Foundation of China(22002088);International Cooperation Program of Shanghai Science and Technology Committee(17520711200);Shanghai Sailing Program(20YF1420500)

摘要:

近年来, 全世界达成了减少温室气体排放、防止气候恶化的共识. 二氧化碳电还原(CO2RR)是利用可再生能源产生的电能将CO2气体转化为高能量密度化学品的方案, 可实现CO2的有效利用和可再生能源的存储, 是其实现碳循环的有效途径. CO2RR过程涉及多个电子转移与质子耦合, 该反应体系复杂, 中间产物覆盖度低, 因此长期以来有关其电催化机理研究是一个挑战性难题. 同时, CO2RR过程中催化剂结构演变、活性位点的识别、电解质的作用机制和吸附态CO角色等问题仍存在争议. 原位振动光谱可用于监测界面上CO2还原反应过程中催化剂结构演变、捕获弱吸附的中间产物, 能够为理清反应机制和反应路径提供关键信息.

本综述介绍了原位振动光谱包括红外、拉曼和和频光谱等对CO2RR中关键基本问题的解决策略, 主要包括: (1)揭示了不同电极上CO2RR的反应中间体和反应路径; (2)探讨了CO在CO2RR中的角色, 包括CO的吸附构型、覆盖度以及作为分子探针的作用; (3)明确了催化剂(主要Cu基催化剂)的结构与组成对CO2RR活性和选择性的影响; (4)讨论了CO2RR过程阴、阳离子对界面局部电场和pH, 以及反应中间体的影响.

CO2RR过程的复杂性为该领域的研究带来了更多的挑战和机遇, 本文对原位振动光谱的未来发展和应用策略提出以下建议: (1)发展和应用能涵盖指纹区检测的高灵敏宽频红外光谱技术, 获取更多更可靠的中间物种和产物信息; (2)耦合多种原位和在线谱学方法深入揭示CO2还原催化剂构效关系; (3)发展和应用适合于膜电极体系的振动光谱技术, 探索工况条件下的CO2RR反应机制.

关键词: 二氧化碳电还原, 电催化机制, 振动光谱, 中间体, 构效关系, 电解质效应

Abstract:

Using renewable energy to drive carbon dioxide reduction reaction (CO2RR) electrochemically into chemicals with high energy density is an efficient way to achieve carbon neutrality, where the effective utilization of CO2 and the storage of renewable energy are realized. The reactivity and selectivity of CO2RR depend on the structure and composition of the catalyst, applied potential, electrolyte, and pH of the solution. Besides, multiple electron and proton transfer steps are involved in CO2RR, making the reaction pathways even more complicated. In pursuit of molecular-level insights into the CO2RR processes, in situ vibrational methods including infrared, Raman and sum frequency generation spectroscopies have been deployed to monitor the dynamic evolution of catalyst structure, to identify reactive intermediates as well as to investigate the effect of local reaction environment on CO2RR performance. This review summarizes key findings from recent electrochemical vibrational spectrosopic studies of CO2RR in addressing the following issues: the CO2RR mechanisms of different pathways, the role of surface-bound CO species, the compositional and structural effects of catalysts and electrolytes on CO2RR activity and selectivity. Our perspectives on developing high sensitivity wide-frequency infrared spectroscopy, coupling different spectroelectrochemical methods and implementing operando vibrational spectroscopies to tackle the CO2RR process in pilot reactors are offered at the end.

Key words: Carbon dioxide electroreduction reaction, Electrocatalytic mechanism, Vibrational spectroscopy, Intermediate, Structure-performance relation, Electrolyte effect