On the nanoparticle synthesis in microemulsions: detailed characterizationof an applied reaction mixture

Citation
M. Lade et al., On the nanoparticle synthesis in microemulsions: detailed characterizationof an applied reaction mixture, COLL SURF A, 163(1), 2000, pp. 3-15
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
ISSN journal
0927-7757 → ACNP
Volume
163
Issue
1
Year of publication
2000
Pages
3 - 15
Database
ISI
SICI code
0927-7757(20000331)163:1<3:OTNSIM>2.0.ZU;2-E
Abstract
In this study we present well-characterized non-ionic (w/o)-microemulsions as suitable reaction media for the synthesis of nanoparticles. For oil-rich three component systems of water, cyclohexane and Marlipal surfactants, we determined the phase behavior, the viscosity, the droplet size and the int erdroplet exchange rates. The general influence of the particular microemul sion properties on the mechanism of nanoparticle formation is discussed on the basis of the LaMer model for particle formation. As the nucleation, par ticle growth and aggregation are controlled by the droplet exchange process , all these steps are retarded in comparison to a homogeneous solution. Thi s retardation causes a particle growth that is not accompanied by aggregati on of nuclei. Therefore, a higher number of nuclei is maintained during the precipitation that grows to smaller particles than have been expected for a precipitation in a homogeneous solution. Therefore, we assume that for al l precipitation reactions, where the growth step is diffusion controlled an d aggregation of nuclei reduces the number of particles, the application of a microemulsion as precipitation medium yields much smaller particles than obtained from homogeneous solutions. (C) 2000 Elsevier Science B.V. All ri ghts reserved.