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Dislocations, crystallite size, and planar faults in nanocrystalline ceria

Published online by Cambridge University Press:  29 February 2012

S. R. Aghdaee*
Affiliation:
Department of Physics, Iran University of Science and Technology, Narmak, 716844 Tehran, Iran
V. Soleimanian
Affiliation:
Department of Physics, Iran University of Science and Technology, Narmak, 716844 Tehran, Iran
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]

Abstract

The modified Williamson–Hall and Warren–Averbach methods were used successfully for analyzing experimentally observed anisotropic X-ray diffraction line broadening and for determining reliable values of crystallite size and dislocation density in cerium oxide. The modified Williamson–Hall plot gives 22.3(2) nm for volume-weighted crystallite size, while the modified Warren–Averbach produces 18.0(2) nm for area-weighted grain size. The dislocation density and effective outer cut-off radius of dislocations obtained from the modified Warren–Averbach method are 1.8(3)×1015 m−2 and 15.5(1) nm, respectively.

Type
Technical Articles
Copyright
Copyright © Cambridge University Press 2009

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