催化学报 ›› 2023, Vol. 53: 52-71.DOI: 10.1016/S1872-2067(23)64543-7

• 综述 • 上一篇    下一篇

电催化CO2还原过程中非均相界面的动态行为

申珅玉a, 郭庆丰b, 武甜甜a,*(), 苏亚琼a,*()   

  1. a西安交通大学化学学院, 储能材料与器件教育部工程研究中心, 储能技术产教融合国家创新平台(中心), 陕西西安710049
    b黄河科技学院, 河南郑州450063
  • 收稿日期:2023-07-29 接受日期:2023-09-20 出版日期:2023-10-18 发布日期:2023-10-25
  • 通讯作者: *电子信箱: tianwu@xjtu.edu.cn (武甜甜); yqsu1989@xjtu.edu.cn (苏亚琼).
  • 基金资助:
    国家自然科学基金(22103059)

The dynamic behaviors of heterogeneous interfaces in electrocatalytic CO2 reduction

Shenyu Shena, Qingfeng Guob, Tiantian Wua,*(), Yaqiong Sua,*()   

  1. aSchool of Chemistry, Engineering Research Center of Energy Storage Materials and Devices of Ministry of Education, National Innovation Platform (Center) for Industry-Education Integration of Energy Storage Technology, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China
    bHuanghe Science and Technology College, Zhengzhou 450063, Henan, China
  • Received:2023-07-29 Accepted:2023-09-20 Online:2023-10-18 Published:2023-10-25
  • Contact: *E-mail: tianwu@xjtu.edu.cn (T. Wu); yqsu1989@xjtu.edu.cn (Y. Su).
  • About author:Tiantian Wu received her Ph.D. from Technical University of Denmark in 2019, and then worked as a postdoc in Technical University of Denmark from 2019 to 2021. She also had an external stay at Prof. Núria López’s group in Institute of Chemical Research of Catalonia (ICIQ), the Barcelona Institute of Science and Technology. Now she is working as an assistant professor in Xi’an Jiaotong University. Her research area is computational catalysis in metal-air batteries, lithium-ion batteries, and electrocatalysis in solid fuel cells (SOECs).
    Yaqiong Su received his Master degree from Xiamen University in 2014 and PhD degree from Eindhoven University of Technology in 2019, and then did his postdoctoral research at Eindhoven University of Technology in 2019. He worked as a visiting scholar in 2011-iChEM, Xiamen University from November 2019 to August 2020. He is now a distinguished professor and principal investigator at Xi’an Jiaotong University. His research involves theoretical chemistry, computational catalysis and spectroscopic electrochemistry.
  • Supported by:
    The National Natural Science Foundation of China(22103059)

摘要:

自工业革命以来, CO2的过量排放导致了环境污染和气候变化, 对人类可持续发展造成了极大的威胁. 由可再生电力驱动的电催化CO2还原反应(CO2RR)技术可在较温和的条件下将CO2转化为高附加价值的燃料和化学品, 因而是一种有效的CO2转换和利用的方法. 尽管电催化CO2RR已经取得了较大的研究进展, 但其工业化应用依旧面临着许多挑战: CO2RR的反应路径涉及多步电子-质子转移, 其产物组分较复杂(包括C1到C3的产物), 并且反应过程伴随着析氢反应(HER)副反应发生. 此外, 不同电催化剂的使用以及实验操作条件均对CO2RR影响较大, 导致目前CO2RR催化剂性能尚不够理想, 因而难以获得实际应用. 为进一步开发性能良好的电催化CO2RR体系, 以及认识实际反应过程中催化体系真正的活性位点, 理解电催化剂表面结构演变机制至关重要.

本文综述了CO2RR条件下非均相催化界面的动态演变行为. 首先, 本文讨论了催化界面动态演变的原理和分类. 催化剂结构在实时工况下会发生演变, 导致活性位点难以确定, 因此需要明确催化界面动态演变的机制. 动态演变行为主要分为催化剂表面形态演变和性质演变: 表面形态演变主要指原子重排或迁移, 该过程由热力学和动力学驱动; 性质演变主要是化学态发生改变, 它是催化剂表面性质和外界环境共同作用的结果. 目前, 大多数的研究都围绕着催化剂表面和次表面活性位点展开, 所讨论的影响催化剂性质的因素主要包括化学组成、晶面和表面形态等. 除催化剂内在性质外, 还详细讨论了影响动态演变的外界环境因素, 包括外加电位、温度、电解质以及杂质等. 外加电位是影响催化界面的主要因素, 电解质中的阴阳离子也对反应选择性有较大的影响. 为了更好地认识反应过程中催化剂表面的活性位点, 总结了光谱表征、X射线表征、微观表征等技术在研究催化界面动态演变行为中的应用. 特别地, 脉冲CO2电解技术可以调节催化界面的动态演变行为, 进而更好地调控反应的活性和选择性. 在此基础上, 理论模拟方法如密度泛函从头算和机器学习等方法, 可以模拟环境条件驱动下的催化剂表面重构, 为动态演变机制提供新的认识.

本文还总结了当前研究电催化还原CO2反应界面的动态演变行为所面临的问题和挑战, 并展望了CO2RR未来的研究方向.

关键词: CO2还原反应, 动态行为, 活性位点, 外界环境, 电催化

Abstract:

The electrocatalytic CO2 reduction reaction (CO2RR) is a highly promising renewable energy technology that can convert greenhouse gases into valuable fuels and chemicals. However, under ordinary operating conditions, significant dynamic evolution behavior occurs on the catalyst surface, which is mainly manifested as surface morphology evolution and property changes, eventually leading to changes in the active sites of the reaction, affecting selectivity and efficiency. To develop efficient electrocatalytic systems with excellent performance, an essential prerequisite is to understand the underlying mechanism of surface dynamic evolution. Studying the influence of the external environment on dynamic evolution is as important as studying the intrinsic structural properties of catalysts. In this review, we first introduce the concept of dynamic evolution and then emphasize the influence of the external environment (applied potential, temperature, electrolyte, and impurities) on CO2RR dynamic evolution. We also address the use of operando characterization techniques and pulsed CO2 electrolysis methods for monitoring and controlling dynamic evolution behaviors under working conditions, along with theoretical methods, including ab initio calculations and machine learning that can simulate dynamic behavior. Finally, we present several current challenges and prospects for the development of techniques for controlling the CO2RR dynamic evolution.

Key words: CO2 reduction reaction, Dynamic behavior, Active site, External environment, Electrocatalysis