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A high-resolution transmission electron microscopy study of defects in γ-Al2O3 nanorods

Published online by Cambridge University Press:  03 March 2011

W.F. Li ,
X.L. Ma ,
Y. Li ,
W.S. Zhang  and
Z.D. Zhang
W.F. Li*
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, and International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
X.L. Ma
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
Y. Li
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
W.S. Zhang
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, and International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
Z.D. Zhang
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, and International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, People’s Republic of China
*
a) Address all correspondence to this author. e-mail: wfli@imr.ac.cn
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Abstract

Surface and planar defect structures of γ-Al2O3 nanorods synthesized by the arc-discharge method were studied by means of high-resolution transmission electron microscopy and image simulation. Our investigation showed that there was a high number density of twins in the nanorods. We suggested a possible configuration of {111} twins in γ-Al2O3, and this model fit our experimental result well. In some nanorods, the ordering of nanotwins gave rise to a local hexagonal-like structure. The twinned nanorods were usually enclosed by {100} and {111} facets, and their growth direction was changed from 〈110〉 into 〈111〉. The surface structures of the nanorods confirmed that the {111}-type surface should be more stable.

Keywords

DefectsNanostructureTransmission electron microscopy (TEM)
Type
Articles
Information
Journal of Materials Research , Volume 22 , Issue 3 , March 2007 , pp. 595 - 602
Copyright
Copyright © Materials Research Society 2007

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References

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