A density functional theory study on the conversion of ethylene to carbon monomer on PdAu(100) surface

作者：Zhang Minhua; Yang Bing; Yu Yingzhe^*

来源：Applied Surface Science, 2015, 356: 1252-1261.

DOI：10.1016/j.apsusc.2015.07.221

• Ethylene decomposition
• PdAu(100)
• Carbon monomer
• Density functional theory

Calculations based on the first-principles density functional theory (DFT) were performed to study the possible transformation pathways of ethylene on PdAu( 1 0 0) surface to investigate the effect of Au atom alloying with Pd on the formation of CHx (x = 0-2), which may eventually form carbon monomer and lead to the deactivation of catalysts. The energetic properties of reactions including the scission of the C-H, C-C bond and a hydrogen-shift process were determined. The C-H bond scission is confirmed to be prone to happen on the studied surface, while it is difficult for the C-C bond scission to occur due to relatively high barriers, the values of which are as high as 2.72-4.62 eV. The activation barriers for all related reactions except for the dehydrogenation of vinyl, vinylidene and acetenyl demonstrate that it is harder for the conversion of ethylene to occur on PdAu( 1 0 0) surface than on Pd( 1 0 0) surface, especially for the C-C bond scission. All the results indicate that the alloying of Au atom with pure Pd catalyst can prevent the formation of carbon monomer, which may notably affect properties of catalysts.

• 出版日期2015-11-30
• 单位天津大学