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Title: Surface diffusion driven morphological instability in free-standing nickel nanorod arrays

Abstract

Metallic nanostructures are thermodynamically unstable due to the excess of energy of large numbers of surface atoms. Morphological instability, such as Rayleigh breakup, sintering, and coalescence, can be observed at a temperature much lower than the bulk melting point of the metal. We study the morphological and crystalline evolution of well-aligned free-standing nickel nanorod arrays at elevated temperatures up to 600 °C. The as-deposited nickel nanorods are faceted with sharp nanotips, which are deformed at annealing temperatures higher than 400 °C due to strong surface diffusion. A mud-crack like pattern is formed in the samples annealed above 400 °C, leading to the generation of interconnected porous structure. Meanwhile, the X-ray diffraction reveals the recrystallization of nickel nanocrystals when annealed from 300 to 600 °C.

Authors:
;  [1]
  1. Department of Physics, Virginia Commonwealth University, PO Box 842000, Richmond, Virginia 23284-2000 (United States)
Publication Date:
OSTI Identifier:
22308512
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ANNEALING; COALESCENCE; DIFFUSION; INSTABILITY; MELTING POINTS; NANOPARTICLES; NANOSTRUCTURES; NICKEL; POROUS MATERIALS; RECRYSTALLIZATION; SINTERING; SURFACES; TEMPERATURE RANGE 0400-1000 K; X-RAY DIFFRACTION

Citation Formats

Alrashid, Ebtihaj, and Ye, Dexian. Surface diffusion driven morphological instability in free-standing nickel nanorod arrays. United States: N. p., 2014. Web. doi:10.1063/1.4884878.
Alrashid, Ebtihaj, & Ye, Dexian. Surface diffusion driven morphological instability in free-standing nickel nanorod arrays. United States. doi:10.1063/1.4884878.
Alrashid, Ebtihaj, and Ye, Dexian. 2014. "Surface diffusion driven morphological instability in free-standing nickel nanorod arrays". United States. doi:10.1063/1.4884878.
@article{osti_22308512,
title = {Surface diffusion driven morphological instability in free-standing nickel nanorod arrays},
author = {Alrashid, Ebtihaj and Ye, Dexian},
abstractNote = {Metallic nanostructures are thermodynamically unstable due to the excess of energy of large numbers of surface atoms. Morphological instability, such as Rayleigh breakup, sintering, and coalescence, can be observed at a temperature much lower than the bulk melting point of the metal. We study the morphological and crystalline evolution of well-aligned free-standing nickel nanorod arrays at elevated temperatures up to 600 °C. The as-deposited nickel nanorods are faceted with sharp nanotips, which are deformed at annealing temperatures higher than 400 °C due to strong surface diffusion. A mud-crack like pattern is formed in the samples annealed above 400 °C, leading to the generation of interconnected porous structure. Meanwhile, the X-ray diffraction reveals the recrystallization of nickel nanocrystals when annealed from 300 to 600 °C.},
doi = {10.1063/1.4884878},
journal = {Journal of Applied Physics},
number = 4,
volume = 116,
place = {United States},
year = 2014,
month = 7
}
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