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Title: Crystallography at the nanoscale: planar defects in ZnO nanospikes
The examination of anisotropic nanostructures, such as wires, platelets or spikes, inside a transmission electron microscope is normally performed only in plan view. However, intrinsic defects such as growth twin interfaces could occasionally be concealed from direct observation for geometric reasons, leading to superposition. This article presents the shadow-focused ion-beam technique to prepare multiple electron-beam-transparent cross-section specimens of ZnO nanospikes, via a procedure which could be readily extended to other anisotropic structures. In contrast with plan-view data of the same nanospikes, here the viewing direction allows the examination of defects without superposition. By this method, the coexistence of two twin configurations inside the wurtzite-type structure is observed, namely [2 {\overline 1} {\overline 1} 0]^{\rm W}/(0 1 {\overline 1} 1) and [2 {\overline 1} {\overline 1} 0]^{\rm W}/(0 1 {\overline 1} 3), which were not identified during the plan-view observations owing to superposition of the domains. The defect arrangement could be the result of coalescence twinning of crystalline nuclei formed on the partially molten Zn substrate during the flame-transport synthesis. Three-dimensional defect models of the twin interface structures have been derived and are correlated with the plan-view investigations by simulation.  more » « less
Award ID(s):
1710214
PAR ID:
10200511
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Applied Crystallography
Volume:
52
Issue:
5
ISSN:
1600-5767
Page Range / eLocation ID:
1009 to 1015
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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