### 光电催化二氧化碳还原研究进展

1. 1 湖南大学化学化工学院，化学/生物传感与化学计量学国家重点实验室，化石能源低碳化高效利用湖南省重点实验室，湖南 长沙 410082
2 湖南工程学院化学与化学工程学院，湖南 湘潭 411104
• 收稿日期:2019-06-13 录用日期:2019-08-13 发布日期:2019-08-19
• 通讯作者: 尹双凤 E-mail:sf_yin@hnu.edu.cn
• 作者简介:尹双凤，1996年在北京化工大学获得学士学位，1999年在中石化石油化工科学研究院获得硕士学位，2003年在清华大学获得博士学位。2006年晋升为湖南大学教授。2008年至2009年在香港浸会大学和日本综合工业技术研究所任高级访问学者。现任湖南大学化学与化工学院教授、博导。研究方向：光催化、小分子烃催化转化及新材料研究
• 基金资助:
国家自然科学基金(21725602);国家自然科学基金(21476065);国家自然科学基金(21671062);国家自然科学基金(21776064);湖南省创新研究群体(2019JJ10001);湖南省研究生科研创新项目(CX2018B193)

### Progress in Photoelectrocatalytic Reduction of Carbon Dioxide

Wei Zhou1,Jun-Kang Guo1,Sheng Shen1,Jinbo Pan1,Jie Tang1,Lang Chen1,Chak-Tong Au2,Shuang-Feng Yin1,*()

1. 1 State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Provincial Hunan Key Laboratory for Cost-Effective Utilization of Fossil Fuel Aimed at Reducing Carbon-Dioxide Emissions, Hunan University, Changsha 410082, P. R. China
2 College of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, Hunan Province, P. R. China
• Received:2019-06-13 Accepted:2019-08-13 Published:2019-08-19
• Contact: Shuang-Feng Yin E-mail:sf_yin@hnu.edu.cn
• Supported by:
the National Natural Science Foundation of China(21725602);the National Natural Science Foundation of China(21476065);the National Natural Science Foundation of China(21671062);the National Natural Science Foundation of China(21776064);Innovative Research Groups of Hunan Province, China(2019JJ10001);Hunan Provincial Innovation Foundation for Postgraduate, China(CX2018B193)

CO2是最常见的化合物，作为潜在的碳一资源，可用于制备多种高附加值的化学品，如一氧化碳、甲烷、甲醇、甲酸等。传统的热催化转化CO2方法能耗高，反应条件苛刻。因此，如何在温和条件下高效地将CO2转化成高附加值的化学品，一直以来是催化领域的研究热点和难点之一。光催化技术反应条件温和、绿色环保。然而，纯光催化反应普遍存在太阳能利用效率有限，光生载流子分离效率低等问题。针对上述问题，在光催化的基础上引入电催化，可以提高载流子的分离效率，在较低的过电位下，实现多电子、质子向CO2转移，从而提高催化反应效率。总之，光电催化技术可以结合光催化和电催化的优势，提高CO2催化还原反应效率，为清洁、绿色利用CO2提供了一种新方法。本文依据光电催化CO2还原反应基本过程，从光吸收、载流子分离和界面反应等三个角度综述了光电催化反应的基本强化策略，并对未来可能的研究方向进行了展望。

Abstract:

Carbon dioxide is the most common compound. As a potential source of carbon, it can be used to prepare a variety of high value-added chemicals, such as carbon monoxide, methane, methanol, and formic acid. The traditional method of thermal catalytic conversion of CO2 requires high energy consumption and harsh reaction conditions. Therefore, the efficient conversion of CO2 to value-added chemicals under mild conditions has long been an area of great interest in the field of catalysis. Photocatalysis usually takes place under mild reaction conditions and is environmentally friendly. However, pure photocatalytic reactions generally have a limited solar energy utilization efficiency and low separation efficiency of photogenerated charge carriers. In view of the above problems, the introduction of electrocatalysis on the basis of photocatalysis can improve the charge separation efficiency. At a lower overpotential, multi-electrons and protons can be transferred to CO2, thus improving the catalytic reaction efficiency. Photoelectrochemical catalysis combines the advantages of photocatalysis and electrocatalysis to improve the efficiency of the catalytic reduction of CO2, offering a new method for the clean utilization of CO2. According to the principle of photocatalysis, the absorption capacity of a semiconductor is governed by its band structure. Optimization of the band structure is a major strategy to enhance the absorptivity of photocatalysts. In addition, the loading of light-absorbent materials on photocatalysts is an effective way to enhance the photocatalytic absorption of a photocatalytic system. During photoelectrocatalytic CO2 reduction, numerous photogenerated charge carriers recombine in bulk and on the surface of the catalyst, greatly reducing the efficiency of the catalytic reaction. Therefore, increasing the separation efficiency of charge carriers is an important means to improve the photoelectrocatalytic efficiency. In photoelectrocatalytic CO2 reduction, heterojunction construction and electric field formation often lead to the efficient separation of charge carriers. The interfacial reaction is a crucial step in the photoelectrocatalytic process. After generation, the photogenerated charge carriers need to migrate to the surface of the catalyst to participate in the redox reaction. In photoelectrocatalytic CO2 reduction, electrons participate in the reduction of CO2, while holes participate in the oxidation of water. Studies show that acceleration of the interfacial reaction process is of paramount importance for improving the efficiency of the photoelectrocatalytic reduction of CO2. This review summarizes the basic enhancement strategies of photoelectrocatalytic CO2 reduction from three aspects: light absorption, charge separation, and surface reaction, based on the basic mechanism of the reduction. The future prospects and research areas are also proposed.

MSC2000:

• O643