物理化学学报 >> 2021, Vol. 37 >> Issue (5): 2010040.doi: 10.3866/PKU.WHXB202010040

所属专题: CO2还原

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二氧化碳电还原反应的理论研究

苑琦, 杨昊, 谢淼, 程涛()   

  • 收稿日期:2020-10-19 录用日期:2020-11-30 发布日期:2020-12-10
  • 通讯作者: 程涛 E-mail:tcheng@suda.edu.cn
  • 作者简介:程涛,1984年7月。2012年于上海交通大学获得化学博士学位。现受聘于苏州大学功能纳米与软物质学院。主要研究方向为理论计算化学。主要研究领域为利用基于量子化学的多尺度模拟方法研究重要的催化和能源问题,如二氧化碳电还原、燃料电池、锂金属电池等
  • 基金资助:
    国家自然科学基金(21975148);江苏省自然科学基金(SBK20190810)

Theoretical Research on the Electroreduction of Carbon Dioxide

Qi Yuan, Hao Yang, Miao Xie, Tao Cheng()   

  • Received:2020-10-19 Accepted:2020-11-30 Published:2020-12-10
  • Contact: Tao Cheng E-mail:tcheng@suda.edu.cn
  • About author:Tao Cheng, Email: tcheng@suda.edu.cn; Tel.: +86-512-65885861
  • Supported by:
    the National Natural Science Foundation of China(21975148);the Natural Science Foundation of Jiangsu Higher Education Institutions(SBK20190810)

摘要:

通过电能将二氧化碳转化为高附加值的工业产品:一方面有利于大幅度减少空气中二氧化碳这类温室气体的含量,同时也实现了电能到化学能的转化,实现电化学储能。尽管对二氧化碳电化学还原的研究已经有三十多年,但仍然缺乏高效地将二氧化碳电化学还原的催化剂。目前,已报道的研究体系在催化性能上远远无法满足工业生产的要求。为了开发制备更高效的二氧化碳电化学还原催化剂,深入理解二氧化碳电还原反应机理至关重要。在研究电化学反应机理方面,理论模拟可以从原子水平提供基元反应的反应细节和能量信息,补充了实验无法提供的微观反应机理。一方面解释了已有实验现象,另一方面也为反应机理的研究提供了新的认识。在此基础上,利用高通量计算和机器学习这些新的研究范式,为加速材料开发提供了理性设计的新思路。在本工作中,我们将对近些年来二氧化碳电还原方面的理论研究工作进行系统性的总结。

关键词: 二氧化碳, 电化学, 还原反应, 理论模拟, 非均相催化

Abstract:

Converting CO2 into value-added products via sustainable energy, such as electrical energy, has several advantages. First, it is one of the most promising routes to close the carbon loop and plays a crucial role in significantly reducing the CO2 concentration in the atmosphere. Second, it can utilize CO2 as a valuable industry reactant that can store energy by converting electrical energy to chemical energy. Although the CO2 reduction reaction has been studied for more than three decades, the sluggish kinetics remain a bottleneck, which requires a highly efficient catalyst. However, none of the reported catalysts meets the requirements for any practical application due to low activity and poor selectivity. To rationally design a more efficient CO2 reduction catalyst, understanding the reaction mechanism is crucial. Although it is challenging to experimentally capture and characterize the reactive intermediates, atomic modeling serves as an alternative for providing an understanding of the elementary reactions on a microscale. Significant progress has been made in understanding the reaction mechanism using multiscale simulations. In this study, important progress in revealing the reaction mechanism of CO2 reduction using computational simulation in recent years is summarized. First, the advances in simulation methods for electrochemical reactions are introduced, and the advantages and disadvantages of various methods are compared. Second, the detailed reaction mechanism of CO2 reduction to various major products, such as CO, CH4, and C2H4, and minor products, such as ethanol and acetate, are disused. Different results obtained from different approximations are compared, while a mechanism that can better explain the existing experimental results is recommended. Third, the operando technique, such as ambient pressure X-ray photoelectron spectroscopy, is disused. The operando analysis results are direct evidence to validate the theoretically proposed reaction pathway. In turn, the theoretical predictions can help resolve the experimental spectrum, which is usually too complex to refer to a reference system. The combination of theory and operando experiments should be one of the most promising directions in determining the reaction mechanism. Fourth, novel synthesis strategies are discussed. These new ideas are beneficial for simplifying the synthesis process or increasing the diversity of products. Finally, the recent progress in the application of machine learning to big data for CO2 reduction is discussed. These new powerful tools may play a crucial role in reaction mechanism studies. Overall, in the study of electrochemical reaction mechanism, theoretical simulation can provide the reaction details and energy information of elementary reactions at the atomic level. Therefore, in the study of electrochemical reaction mechanism of carbon dioxide, the microscopic mechanism that the experiment cannot provide is supplemented. On the one hand, it explains the existing experimental phenomena; however, on the other hand, it provides new insights for the study of reaction mechanism. On this basis, the use of new research paradigms, such as high-throughput computing and machine learning, provides new ideas for a rational design for accelerating material development.

Key words: Carbon dioxide, Electrochemistry, Reduction reaction, Theoretical simulation, Heterogeneous catalysis

MSC2000: 

  • O643