Computational Investigation of CO Adsorption and Oxidation on Mn/CeO2(111) Surface

详细信息    查看全文

• 作者：Ling-Chieh Hsu ; Ming-Kang Tsai ; Yu-Huan Lu ; Hsin-Tsung Chen
• 刊名：The Journal of Physical Chemistry C
• 出版年：2013
• 出版时间：January 10, 2013
• 年：2013
• 卷：117
• 期：1
• 页码：433-441
• 全文大小：545K
• 年卷期：v.117,no.1(January 10, 2013)
• ISSN：1932-7455

文摘

The interaction and mechanism for CO oxidation on the Mn/CeO₂(111) surface have been studied by using periodic density functional theory calculations corrected with the on-site Coulomb interaction via a Hubbard term (DFT + U). It is found that the Mn dopant facilitates oxygen vacancy formation, while the Mn adatoms may restrain oxygen vacancy formation. In addition, physisorbed CO, physisorbed CO₂ ,and chemisorbed CO (carbonite, CO₂^{鈥?/sup>) species are observed on the Mn-doped CeO₂(111) surface, in contrast, only physisorbed CO is found on the pure CeO₂(111) surface. The vibrational frequency calculations as well as the calculated adsorption energies are carried to characterize these species. The Mn dopant promotes CO oxidation without any activation energy leading to O vacancy formation and CO₂ desorption. The Bader charge analysis is carried to characterize the oxidation state of Mn ions along the catalytic cycle.}