Density functional study of selective oxidation of ethanol over silver catalysts

被引:0
作者
Xu X. [1 ]
Tian P. [1 ]
Xu J. [1 ]
Han Y. [1 ]
机构
[1] State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai
来源
Huagong Xuebao/CIESC Journal | 2019年 / 70卷 / 10期
关键词
Catalysis; Molecular simulation; Partial oxidation; Silver;
D O I
10.11949/0438-1157.20190480
中图分类号
学科分类号
摘要
A systematic study on the catalytic oxidation of Ag(111) and Ag(211) on the surface of Ag(111) was carried out by density functional theory. It was found that atomic O* is necessary to initiate the reaction at the ambient conditions. The O-H bond in the ethanol is activated with the help of adsorbed atomic O* to form ethoxy, which then further transfers hydrogen in α-C-H to adsorbed O* forming the acetaldehyde (Ea<38 kJ/mol), which, in turn, reacts with atomic O*/OH* to form final product CO2. To generate CO2, C-C bond breaking (CCOO→C+CO2 on Ag(111) and CH2COO→CH2+ CO2 on Ag(211)) exhibits the highest barriers (Ea>95.5 kJ/mol), which indicated it is the rate-determining step. The results indicate that the catalytic oxidation of ethanol on silver surfaces is structural sensitive. Selectivity towards value-added products like acetaldehyde would be improved by reducing the density of defected sites. © All Right Reserved.
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页码:3967 / 3975
页数:8
相关论文
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