Size-dependent melting of silica-encapsulated gold nanoparticles
(2002) In Journal of the American Chemical Society 124(10). p.2312-2317- Abstract
We report on the size dependence of the melting temperature of silica-encapsulated gold nanoparticles. The melting point was determined using differential thermal analysis (DTA) coupled to thermal gravimetric analysis (TGA) techniques. The small gold particles, with sizes ranging from 1.5 to 20 nm, were synthesized using radiolytic and chemical reduction procedures and then coated with porous silica shells to isolate the particles from one another. The resulting silica-encapsulated gold particles show clear melting endotherms in the DTA scan with no accompanying weight loss of the material in the TGA examination. The silica shell acts as a nanocrucible for the melting gold with little effect on the melting temperature itself, even... (More)
We report on the size dependence of the melting temperature of silica-encapsulated gold nanoparticles. The melting point was determined using differential thermal analysis (DTA) coupled to thermal gravimetric analysis (TGA) techniques. The small gold particles, with sizes ranging from 1.5 to 20 nm, were synthesized using radiolytic and chemical reduction procedures and then coated with porous silica shells to isolate the particles from one another. The resulting silica-encapsulated gold particles show clear melting endotherms in the DTA scan with no accompanying weight loss of the material in the TGA examination. The silica shell acts as a nanocrucible for the melting gold with little effect on the melting temperature itself, even though the analytical procedure destroys the particles once they melt. Phenomenological thermodynamic predictions of the size dependence of the melting point of gold agree with the experimental observation. Implications of these observations to the self-diffusion coefficient of gold in the nanoparticles are discussed, especially as they relate to the spontaneous alloying of core - shell bimetallic particles.
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- author
- Dick, Kimberly LU ; Dhanasekaran, T. ; Zhang, Zhenyuan and Meisel, Dan
- publishing date
- 2002-03-13
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of the American Chemical Society
- volume
- 124
- issue
- 10
- pages
- 6 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- pmid:11878986
- scopus:0037070541
- ISSN
- 0002-7863
- DOI
- 10.1021/ja017281a
- language
- English
- LU publication?
- no
- id
- df8e21e4-c9e5-4a1c-9ca1-a10362b28fbd
- date added to LUP
- 2022-02-11 14:46:01
- date last changed
- 2024-04-23 21:59:48
@article{df8e21e4-c9e5-4a1c-9ca1-a10362b28fbd,
abstract = {{<p>We report on the size dependence of the melting temperature of silica-encapsulated gold nanoparticles. The melting point was determined using differential thermal analysis (DTA) coupled to thermal gravimetric analysis (TGA) techniques. The small gold particles, with sizes ranging from 1.5 to 20 nm, were synthesized using radiolytic and chemical reduction procedures and then coated with porous silica shells to isolate the particles from one another. The resulting silica-encapsulated gold particles show clear melting endotherms in the DTA scan with no accompanying weight loss of the material in the TGA examination. The silica shell acts as a nanocrucible for the melting gold with little effect on the melting temperature itself, even though the analytical procedure destroys the particles once they melt. Phenomenological thermodynamic predictions of the size dependence of the melting point of gold agree with the experimental observation. Implications of these observations to the self-diffusion coefficient of gold in the nanoparticles are discussed, especially as they relate to the spontaneous alloying of core - shell bimetallic particles.</p>}},
author = {{Dick, Kimberly and Dhanasekaran, T. and Zhang, Zhenyuan and Meisel, Dan}},
issn = {{0002-7863}},
language = {{eng}},
month = {{03}},
number = {{10}},
pages = {{2312--2317}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Journal of the American Chemical Society}},
title = {{Size-dependent melting of silica-encapsulated gold nanoparticles}},
url = {{http://dx.doi.org/10.1021/ja017281a}},
doi = {{10.1021/ja017281a}},
volume = {{124}},
year = {{2002}},
}