A DFT Study on the Catalytic CO Oxidative Coupling to Dimethyl Oxalate on Al-Doped Core-Shell Pd Clusters

作者：Feng, Xue; Ling, Lixia^*; Can, Yueting; Zhang, Riguang; Fan, Maohong; Wang, Baojun^*

来源：Journal of Physical Chemistry C, 2018, 122(2): 1169-1179.

DOI：10.1021/acs.jpcc.7b09272

• OXYGEN-REDUCTION ELECTROCATALYSTS
• PLATINUM MONOLAYER
• REACTION-MECHANISM
• DIETHYL OXALATE
• CARBON-MONOXIDE
• PALLADIUM
• NANOPARTICLES
• CU
• ADSORPTION
• SIZE

A series of core-shell catalysts aiming at CO oxidative coupling to dimethyl oxalate (DMO) were constructed, and effects of the second metal doping and surface structures on the reaction activity and favorable reaction path were investigated by using the density functional theory (DFT) method. Pd-13, Al@Pd-12, and Ag@Pd-12 were first studied to find the proper doping metal. Our results showed that the activity of CO oxidative coupling to DMO follows the order of Al@Pd-12 > Pd-13 > Ag@Pd-12, and the same result was also obtained via the electronic analysis. In addition, Al-6@Pd-32 and Al-13@Pd-42 catalysts with higher doping ratio and lower cost than that of Al@Pd-12 were selected to examine the influence of surface structure on the reaction activity. It showed that CO + CH3O -> COOCH3 + CO -> OCCOOCH3 + CH3O -> DMO is the favorable pathway on the (100) surface of Al-6@Pd-32 catalyst, while CO + CH3O -> CO + CH3O (COOCH3) -> COOCH3 + COOCH3 -> DMO is the optimal pathway on the (111) surface of Al@Pd-12 and Al-13@Pd-42, which indicated that the surface structure of catalysts affected the preferable pathway of DMO formation. Moreover, activities of CO oxidative coupling to DMO on AlPd core-shell catalysts followed the order of Al@Pd-12 > Al-13@Pd-42 > Al-6@Pd-32. In addition, Al-13@Pd-42 also exhibited a good selectivity between DMO and DMC. Thus, Al-13@Pd-42 is a proper catalyst with high activity, high selectivity, and low cost because of high Al:Pd ratio.

• 出版日期2018-1-18
• 单位太原理工大学