文献类型：期刊文献

英文题名：First-Principles Determination of CO Adsorption and Desorption on Pt(111) in the Free Energy Landscape

作者：Guo, Chenxi[1];Wang, Ziyun[1];Wang, Dong[2,3];Wang, Hai-Feng[2,3];Hu, P.[1,2,3]

机构：[1]Queens Univ Belfast, Sch Chem & Chem Engn, Belfast BT9 5AG, Antrim, North Ireland;[2]East China Univ Sci & Technol, Key Lab Adv Mat, Res Inst Ind Catalysis, Shanghai 200237, Peoples R China;[3]East China Univ Sci & Technol, Ctr Computat Chem, Shanghai 200237, Peoples R China

年份：2018

卷号：122

期号：37

起止页码：21478

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY C

收录：;EI(收录号：20183805835879);WOS:【SCI-EXPANDED(收录号:WOS:000445711100040)】；

基金：UK Archer provides supercomputing service. C.X.G. thanks the Queen's University of Belfast and China Scholarship Council for finance support. This project was supported by the National Natural Science Foundation of China (21333003 and 21622305), Young Elite Scientist Sponsorship Program by CAST (YESS20150131), "Shu Guang" project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation (17SG30), and the Fundamental Research Funds for the Central Universities (WJ616007).

语种：英文

外文关键词：Calculations - Platinum compounds - Adsorption - Molecular dynamics - Catalysis - Free energy - Reaction kinetics

摘要：Traditionally, catalytic processes are calculated using the total energy approach from density functional theory (DFT), and the method to determine the barriers of the adsorption/desorption from DFT calculations is thus still not available. In this work, we choose CO adsorption/desorption on Pt(111) as a model for two reasons. First, it is often a rate-limiting step in many catalytic reactions. Second, the disagreement between the experiment and DFT calculations on the CO adsorption sites of Pt(111) has been known as "the CO puzzle" in the literature, and to further understand the puzzle is desirable. We introduce a molecular dynamics method within the framework of DFT, allowing us to calculate the free energy barriers of adsorption/desorption without experimental inputs. Our results show that the top site is more preferred for CO adsorption in terms of free energy, which agree with experimental work, but in contrast to the traditional DFT total energy calculations. A delocalized nature of CO chemisorption on the hollow site is found, and the key reason for the discrepancy between the free energy simulations and the total energy calculations is identified, which may have some profound implications in total energy calculations in general.