Publication
Title
Do binary supracrystals enhance the crystal stability?
Author
Abstract
We study the oxygen thermal stability of two binary systems. The larger particles are magnetic amorphous Co (7.2 nm) or Fe3O4 (7.5 nm) nanocrystals, whereas the smaller ones (3.7 nm) are Au nanocrystals. The nanocrystal ordering as well as the choice of the magnetic nanoparticles very much influence the stability of the binary system. A perfect crystalline structure is obtained with the Fe3O4/Au binary supracrystals. For the Co/Au binary system, oxidation of Co results in the chemical transformation from Co to CoO, where the size of the amorphous Co nanoparticles increases from 7.2 to 9.8 nm in diameter. During the volume expansion of the Co nanoparticles, Au nanoparticles within the binary assemblies coalesce and are at the origin of the instability of the binary nanoparticle supracrystals. On the other hand, for the Fe3O4/Au binary system, the oxidation of Fe3O4 to γ-Fe2O3 does not lead to a size change of the nanoparticles, which maintains the stability of the binary nanoparticle supracrystals. A similar behavior is observed for an AlB2-type CoAg binary system: The crystalline structure is maintained, whereas in disordered assemblies, coalescence of Ag nanocrystals is observed.
Language
English
Source (journal)
The journal of physical chemistry: C : nanomaterials and interfaces. - Washington, D.C., 2007, currens
Publication
Washington, D.C. : 2018
ISSN
1932-7447 [print]
1932-7455 [online]
DOI
10.1021/ACS.JPCC.7B12373
Volume/pages
122 :25 (2018) , p. 13515-13521
ISI
000437811500035
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Project info
SUPRANANO: From metal nanocrystal to supracrystal:crystallinity at nanometer and micrometer scales
European Soft Matter Infrastructure (ESMI).
Colouring Atoms in 3 Dimensions (COLOURATOM).
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identifier
Creation 06.03.2018
Last edited 09.10.2023
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