CO2在Cu表面还原成碳氢化合物的DFT计算研究

CORC > 厦门大学 > 2011年第17卷

	CO2在Cu表面还原成碳氢化合物的DFT计算研究; DFT Study of CO2 Reduction to Hydrocarbons on Cu Surfaces
	欧利辉 ; 陈胜利 ; Ou Li-Hui ; CHEN Sheng-Li
刊名	http://electrochem.xmu.edu.cn/CN/abstract/abstract9792.shtml
	2011-05-28
关键词	密度泛函理论计算 CO2还原反应路径 Density functional theory calculations Carbon dioxide reduction The minimum energy paths
英文摘要	应用密度泛函理论（DFT）反应能计算及最小能量路径分析研究了CO2在气相和电化学环境中于Cu(111)单晶表面的还原过程。气相中，CO2还原为碳氢化合物的反应路径可能为：CO2(g) + H* → COOH* → (CO +OH)* → CHO；CHO + H → CH2O* → (CH2 + O)；CH2 + 2H* → CH4或2CH2* → C2H4。整个反应由CO2(g) + H* → COOH* → (CO +OH)，(CO + H) → CHO和CH2O → (CH2 + O)等几个步骤联合控制。在-0.50V (vs RHE) 以正的电势下，CO2在Cu(111)表面电化学还原主要形成HCOO-和CO吸附物；随着电势逐渐负移，CO2加氢解离形成CO的反应越来越容易，CO成为主要产物；随电势进一步变负，形成碳氢化合物的趋势逐渐变强。与CO2的气相化学还原不同的是，电化学环境下CO质子化形成的CHO中间体倾向于解离形成CH，而在气相中CHO中间体则倾向于进一步质子化形成CH2O中间体。; CO2 reduction on Cu(111) single crystal surfaces was studied using DFT calculations on the reaction energies and the minimum energy paths. The results indicated that the possible reaction paths for CO2 reduction on Cu(111) surface are CO2(g) + H → COOH* → (CO +OH), (CO + H) → CHO, CHO + H → CH2O → (CH2 + O), CH2 + 2H* → CH4 or 2CH2* → C2H4. On Cu(111) surface, the reaction rate is controlled by steps of CH2O* → (CH2 + O), CO2(g) + H → COOH → (CO +OH)* and (CO + H)* → CHO*. In addition, the reaction energies for various steps in the electrochemical reduction of CO2 were calculated under different electrode potentials. The results indicated that HCOO- and CO are mainly formed when the potential is more positive than -0.50V (vs. RHE). The hydrogenated dissociation of CO2 to form CO and the subsequent hydrogenation of CO become increasingly exothermic as the potential goes negative, so that hydrocarbons gradually becomes the favored products in the electrochemical reduction. Under electrochemical conditions, the CHO intermediate prefers to dissociate to form CH, rather than to form CH2O intermediate via protonation as does in gas phase reduction.; 国家自然科学基金(21073137, 50632050); 作者联系地址：1. 武汉大学化学与分子科学学院，湖北武汉 430072; 2. 湖南文理学院化学化工学院，湖南常德 415000; Author's Address: 1. College of Chemistry and Molecular Sciences，Wuhan University，Wuhan 430072，Hubei，China; 2. College of Chemistry and Chemical Engineering, Hunan University of Arts and Science, Changde 415000 Hunan, China; 通讯作者E-mail：slchen@whu.edu.cn
语种	中文
出版者	厦门大学《电化学》编辑部
内容类型	期刊论文
源URL	[http://dspace.xmu.edu.cn/handle/2288/58420]
专题	2011年第17卷
推荐引用方式 GB/T 7714	欧利辉,陈胜利,Ou Li-Hui,等. CO2在Cu表面还原成碳氢化合物的DFT计算研究, DFT Study of CO2 Reduction to Hydrocarbons on Cu Surfaces[J]. http://electrochem.xmu.edu.cn/CN/abstract/abstract9792.shtml,2011.
APA	欧利辉,陈胜利,Ou Li-Hui,&CHEN Sheng-Li.(2011).CO2在Cu表面还原成碳氢化合物的DFT计算研究.http://electrochem.xmu.edu.cn/CN/abstract/abstract9792.shtml.
MLA	欧利辉,et al."CO2在Cu表面还原成碳氢化合物的DFT计算研究".http://electrochem.xmu.edu.cn/CN/abstract/abstract9792.shtml (2011).