Screw Dislocation-Driven Growth of Two-Dimensional Nanoplates
Department of Chemistry, University of Wisconsin - Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States. Nano Letters
(Impact Factor: 13.59).
09/2011; 11(10):4449-55. DOI: 10.1021/nl202689m
We report the dislocation-driven growth of two-dimensional (2D) nanoplates. They are another type of dislocation-driven nanostructure and could find application in energy storage, catalysis, and nanoelectronics. We first focus on nanoplates of zinc hydroxy sulfate (3Zn(OH)(2)·ZnSO(4)·0.5H(2)O) synthesized from aqueous solutions. Both powder X-ray and electron diffraction confirm the zinc hydroxy sulfate (ZHS) crystal structure as well as their conversion to zinc oxide (ZnO). Scanning electron, atomic force, and transmission electron microscopy reveal the presence of screw dislocations in the ZHS nanoplates. We further demonstrate the generality of this mechanism through the growth of 2D nanoplates of α-Co(OH)(2), Ni(OH)(2), and gold that can also follow the dislocation-driven growth mechanism. Finally, we propose a unified scheme general to any crystalline material that explains the growth of nanoplates as well as different dislocation-driven nanomaterial morphologies previously observed through consideration of the relative crystal growth step velocities at the dislocation core versus the outer edges of the growth spiral under various supersaturations.
Available from: Sondipon Adhikari
- "Nanoplates such as GS are being found in potential application areas such as in nano-electronic mechanical-systems (NEMS) , nanosensors , nanoactuators , transistor  , solar cells   , biomedical , space elevator lifts in the form of nanoribbons and in nanocomposites. One important technological advancement to the concept of the single or mono nanoplates  is that of the complex-nanoplatesystems . The complex nanoplates can be considered as composite nanostructure. "
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Available from: nanoscience.engr.wisc.edu
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