Evolution of size and shape of gold nanoparticles during long-time aging

The evolution of size and shape of gold nanoparticles was studied during long-time aging. The initial particle size of 2e5 nm increased to about 25 nm in one year of storage. It was revealed that the main mechanism of particle growth is Ostwald ripening, however, fusion of particles was also observed. Additionally, while the initial particles have spherical morphology, the grown particles show various shapes such as sphere, bipyramid, decahedron, deca-tetrahedron, triangular plate and rod. Twin boundaries with large frequency ofw5% were detected inside the particles which have an important effect on the evolution of morphology. This study suggests that aging may be a new way of tuning size and shape of gold nanoparticles
Title: 

Evolution of size and shape of gold nanoparticles during long-time aging
Authors: Gubicza, Jeno
Labar, Janos L.
Luu, Manh Quynh
Keywords: Nanostructures
Crystal growth
Electron microscopy (STEM, TEM and SEM)
Aging
Issue Date: 2013
Publisher: ELSEVIER SCIENCE SA, PO BOX 564, 1001 LAUSANNE, SWITZERLAND
Citation: ISIKNOWLEDGE
Abstract: The evolution of size and shape of gold nanoparticles was studied during long-time aging. The initial particle size of 2e5 nm increased to about 25 nm in one year of storage. It was revealed that the main mechanism of particle growth is Ostwald ripening, however, fusion of particles was also observed. Additionally, while the initial particles have spherical morphology, the grown particles show various shapes such as sphere, bipyramid, decahedron, deca-tetrahedron, triangular plate and rod. Twin boundaries with large frequency ofw5% were detected inside the particles which have an important effect on the evolution of morphology. This study suggests that aging may be a new way of tuning size and shape of gold nanoparticles
Description: MATERIALS CHEMISTRY AND PHYSICS Volume: 138 Issue: 2-3 Pages: 449-453 Published: MAR 15 2013 ; TNS07314
URI: http://www.sciencedirect.com/science/article/pii/S0254058413000564
http://repository.vnu.edu.vn/handle/VNU_123/32824
ISSN: 0254-0584
Appears in Collections:Bài báo của ĐHQGHN trong Web of Science

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