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Size-dependent dynamic structures of supported gold nanoparticles in CO oxidation reaction condition.

Authors :
Yang He
Jin-Cheng Liu
Langli Luo
Yang-Gang Wang
Junfa Zhu
Yingge Du
Jun Li
Mao, Scott X.
Chongmin Wang
Source :
Proceedings of the National Academy of Sciences of the United States of America. 7/24/2018, Vol. 115 Issue 30, p7700-7705. 6p.
Publication Year :
2018

Abstract

Gold (Au) catalysts exhibit a significant size effect, but its origin has been puzzling for a long time. It is generally believed that supported Au clusters are more or less rigid in working condition, which inevitably leads to the general speculation that the active sites are immobile. Here, by using atomic resolution in situ environmental transmission electron microscopy, we report size-dependent structure dynamics of single Au nanoparticles on ceria (CeO2) in CO oxidation reaction condition at room temperature. While large Au nanoparticles remain rigid in the catalytic working condition, ultrasmall Au clusters lose their intrinsic structures and become disordered, featuring vigorous structural rearrangements and formation of dynamic low-coordinated atoms on surface. Ab initio molecular-dynamics simulations reveal that the interaction between ultrasmall Au cluster and CO molecules leads to the dynamic structural responses, demonstrating that the shape of the catalytic particle under the working condition may totally differ from the shape under the static condition. The present observation provides insight on the origin of superior catalytic properties of ultrasmall gold clusters. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
00278424
Volume :
115
Issue :
30
Database :
Academic Search Index
Journal :
Proceedings of the National Academy of Sciences of the United States of America
Publication Type :
Academic Journal
Accession number :
131086531
Full Text :
https://doi.org/10.1073/pnas.1800262115