A novel Pd3O9@α-Al2O3 catalyst under a hydroxylated effect: high activity in the CO oxidation reaction

被引:4
作者
Li, Qiaohong [1 ]
Wei, Yongqin [1 ]
Sa, Rongjian [1 ]
Ma, Zuju [1 ]
Wu, Kechen [1 ]
机构
[1] Chinese Acad Sci, Fujian Inst Res Struct Matter, State Key Lab Struct Chem, Fuzhou 350002, Peoples R China
关键词
SINGLE-ATOM CATALYSIS; DENSITY-FUNCTIONAL THEORY; HEXAGONAL BORON-NITRIDE; ELECTRONIC-PROPERTIES; PD; SURFACE; ADSORPTION; EFFICIENT; MECHANISM; CLUSTER;
D O I
10.1039/c5cp03740a
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
Considering the importance of palladium-based and doped metal-oxide catalysts in CO oxidation, we design a new Pd3O9@alpha-Al2O3 catalyst and simulate its efficiency under a hydroxylated effect. The structure, electronic structure and oxidation activity of the hydroxylated Pd3O9@alpha-Al2O3(0001) surface are investigated by density functional theory. Under the O-rich growth conditions, Pd preferentially replaces Al. The lowest formation energy of the Pd-doped alpha-Al2O3(0001) surface is 0.21 eV under conditions wherein the coverage of the Pd-doped alpha-Al2O3 is 0.75 on a pre-hydroxylated surface and the water coverage is 0.25, which leads to formation of a Pd3O9 cluster embedded in the Al2O3(0001) surface. The reaction mechanisms of CO oxidization have been elucidated first by CO adsorption and migration, second by Ov formation with the first CO2 release, then by the first foreign O-2 filling and CO co-adsorption, and finally by the second CO2 desorption and restoration of the hydroxylated Pd3O9@alpha-Al2O3(0001) surface. The rate-determining step is the formation of the first CO2 in the whole catalytic cycle. The results also indicate that the energy barrier for CO oxidization is obviously reduced compared to that of the undoped surface, which implies that the introduction of Pd can efficiently improve the oxidation reactivity of the alpha-Al2O3(0001) surface. Compared to the synthesized Ir-1/FeOx (1.41 eV) and Pt-1/FeOx (0.79 eV) catalysts, the reaction activation barrier of CO oxidation is lowered by 0.65 eV and 0.03 eV, respectively. Therefore, the Pd3O9@alpha-Al2O3 catalyst shows superior catalytic activity in CO oxidation. The present results enrich the understanding of the catalytic oxidation of CO by palladium-based catalysts and provide a clue for fabricating palladium-based catalysts with low cost and high activity.
引用
收藏
页码:32140 / 32148
页数:9
相关论文
共 61 条
[1]   Energetics of Al doping and intrinsic defects in monoclinic and cubic zirconia: First-principles calculations [J].
Arhammar, C. ;
Araujo, C. Moyses ;
Ahuja, Rajeev .
PHYSICAL REVIEW B, 2009, 80 (11)
[2]   Comparison of the Adsorption of Ni, Pd, and Pt on the (0001) Surface of α-Alumina [J].
Briquet, Ludovic G. V. ;
Catlow, C. Richard A. ;
French, Samuel A. .
JOURNAL OF PHYSICAL CHEMISTRY C, 2008, 112 (48) :18948-18954
[3]   Single-site homogeneous and heterogenized gold(III) hydrogenation catalysts:: Mechanistic implications [J].
Comas-Vives, A ;
González-Arellano, C ;
Corma, A ;
Iglesias, M ;
Sánchez, F ;
Ujaque, G .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2006, 128 (14) :4756-4765
[4]   AN ALL-ELECTRON NUMERICAL-METHOD FOR SOLVING THE LOCAL DENSITY FUNCTIONAL FOR POLYATOMIC-MOLECULES [J].
DELLEY, B .
JOURNAL OF CHEMICAL PHYSICS, 1990, 92 (01) :508-517
[5]   From molecules to solids with the DMol3 approach [J].
Delley, B .
JOURNAL OF CHEMICAL PHYSICS, 2000, 113 (18) :7756-7764
[6]   Single Pd Atom Embedded in CeO2(111) for NO Reduction with CO: A First-Principles Study [J].
Ding, Wu-Chen ;
Gu, Xiang-Kui ;
Su, Hai-Yan ;
Li, Wei-Xue .
JOURNAL OF PHYSICAL CHEMISTRY C, 2014, 118 (23) :12216-12223
[7]   COMPARISON OF THE PERFORMANCE-CHARACTERISTICS OF PT/SNOX AND AU/MNOX CATALYSTS FOR LOW-TEMPERATURE CO OXIDATION [J].
GARDNER, SD ;
HOFLUND, GB ;
UPCHURCH, BT ;
SCHRYER, DR ;
KIELIN, EJ ;
SCHRYER, J .
JOURNAL OF CATALYSIS, 1991, 129 (01) :114-120
[8]   Rh1/-Al2O3 Single-Atom Catalysis of O2 Activation and CO Oxidation: Mechanism, Effects of Hydration, Oxidation State, and Cluster Size [J].
Ghosh, Tushar K. ;
Nair, Nisanth N. .
CHEMCATCHEM, 2013, 5 (07) :1811-1821
[9]   Interaction of Pd with α-Al2O3(0001):: A case study of modeling the metal-oxide interface on complex substrates -: art. no. 125414 [J].
Gomes, JRB ;
Illas, F ;
Hernández, NC ;
Márquez, A ;
Sanz, JF .
PHYSICAL REVIEW B, 2002, 65 (12) :1-9
[10]   Sensitivity of catalysis to surface structure: The example of CO oxidation on Rh under realistic conditions [J].
Gustafson, J. ;
Westerstroem, R. ;
Mikkelsen, A. ;
Torrelles, X. ;
Balmes, O. ;
Bovet, N. ;
Andersen, J. N. ;
Baddeley, C. J. ;
Lundgren, E. .
PHYSICAL REVIEW B, 2008, 78 (04)