title: An In situ TEM study of the surface oxidation of palladium nanocrystals assisted by electron irradiation.
abstract: The surface oxidation of palladium nanocrystals plays an important role in changing the active sites and subsequently influencing the catalytic reactivity. Such a microscopy study on surface oxidation, down to the atomic scale, is essential for understanding the structure-property correlations of palladium nanocrystal based catalysts. Herein, we present an in situ atomic scale study on the surface oxidation behavior of palladium nanocrystals, which is induced by electron beam irradiation under low oxygen partial pressure and at room temperature inside an environmental transmission electron microscope. We found that: (i) surface oxidation initially started at the edge sites with atomic steps or vertex sites, which served as active sites for oxidation; (ii) the oxidation reaction proceeded with a much faster rate on the {111} surface, indicating a certain crystallography preference; (iii) nanometer-sized palladium monoxide islands were formed on the surfaces eventually. The results from our in situ studies provide insightful knowledge, and will be of certain importance for the design of improved functional catalysts in future.
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China. chhjin@zju.edu.cn jx_li@zju.edu.cn.
authors.forename: Dejiong
authors.identifier: http://orcid.org/0000-0002-9009-5992
authors.initials: D
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China. chhjin@zju.edu.cn jx_li@zju.edu.cn.
authors.forename: Chuanhong
authors.identifier: http://orcid.org/0000-0001-8845-5664
authors.initials: C
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China. chhjin@zju.edu.cn jx_li@zju.edu.cn.
authors.forename: He
authors.initials: H
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China. chhjin@zju.edu.cn jx_li@zju.edu.cn.
authors.forename: Yalin
authors.identifier: http://orcid.org/0000-0003-1079-3860
authors.initials: Y
authors.lastname: Xiong
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China. chhjin@zju.edu.cn jx_li@zju.edu.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Lab of Applied Chemistry of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China.
authors.forename: Peisheng
authors.initials: P
authors.lastname: Qiao
authors.affiliation: Key Lab of Applied Chemistry of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China.
authors.forename: Jie
authors.identifier: http://orcid.org/0000-0002-8380-6338
authors.initials: J
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China. chhjin@zju.edu.cn jx_li@zju.edu.cn.
authors.forename: Ze
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Nanoscale Physics Research Laboratory, School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham, B152TT, UK. z.li@bham.ac.uk.
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Li
authors.affiliation: State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, P. R. China. chhjin@zju.edu.cn jx_li@zju.edu.cn.
authors.forename: Jixue
authors.initials: J
authors.lastname: Li