Morphology effect of ceria supports on gold nanocluster catalyzed CO oxidation
The interfacial perimeter is generally viewed as the catalytically active site for a number of chemical reactions over oxide-supported nanogold catalysts. Here, well-defined CeO 2 nanocubes, nanorods and nanopolyhedra are chosen to accommodate atomically precise clusters ( e.g. Au 25 (PET) 18 ) to g...
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Published in | Nanoscale advances Vol. 3; no. 24; pp. 72 - 76 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
RSC
07.12.2021
|
Subjects | |
Online Access | Get full text |
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Summary: | The interfacial perimeter is generally viewed as the catalytically active site for a number of chemical reactions over oxide-supported nanogold catalysts. Here, well-defined CeO
2
nanocubes, nanorods and nanopolyhedra are chosen to accommodate atomically precise clusters (
e.g.
Au
25
(PET)
18
) to give different Au cluster-CeO
2
interfaces. TEM images show that Au particles of ∼1.3 nm are uniformly anchored on the ceria surface after annealing in air at 120 °C, which can rule out the size hierarchy of nanogold in CO oxidation studies. The gold nanoclusters are only immobilized on the CeO
2
(200) facet in Au
25
/CeO
2
-C, while they are selectively loaded on CeO
2
(002) and (111) in the Au
25
/CeO
2
-R and Au
25
/CeO
2
-P catalysts. X-ray photoelectron spectroscopy (XPS) and
in situ
infrared CO adsorption experiments clearly demonstrate that the gold species in the Au
25
/CeO
2
samples are similar and partially charged (Au
δ
+
, where 0 <
δ
< 1). It is observed that the catalytic activity decreases in the order of Au/CeO
2
-R Au/CeO
2
-P > Au/CeO
4
-C in the CO oxidation. And the apparent activation energy over Au
25
/CeO
2
-C (60.5 kJ mol
−1
) is calculated to be about two-fold of that over the Au
25
/CeO
2
-R (28.6 kJ mol
−1
) and Au
25
/CeO
2
-P (31.3 kJ mol
−1
) catalysts. It is mainly tailored by the adsorbed [O] species on the ceria surface, namely, Au
25
/CeO
2
(002) and Au
25
/CeO
2
(111) which were more active than the Au
25
/CeO
2
(200) system in the CO oxidation. These insights at the molecular level may provide guidelines for the design of new oxide-supported nanogold catalysts for aerobic oxidations.
The interfacial perimeter is generally viewed as the catalytically active site for a number of chemical reactions over oxide-supported nanogold catalysts. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 Z. L. and X. Z. contributed equally to this work. |
ISSN: | 2516-0230 2516-0230 |
DOI: | 10.1039/d1na00680k |