The concept of delayed nucleation in nanocrystal growth demonstrated for the case of iron oxide nanodisks.
A comprehensive study of iron oxide nanocrystal growth through non-hydrolitic, surfactant-mediated thermal reaction of iron pentacarbonyl and an oxidizer has been conducted, which includes size control, anisotropic shape evolution, and crystallographic phase transition of monodisperse iron oxide colloidal nanocrystals. The reaction was monitored via in situ UV-vis spectroscopy, taking advantage of the color change accompanying the iron oxide colloid formation, allowing measurement of the induction time for nucleation. Features of the synthesis such as the size control and reproducibility are related to the occurrence of the observed delayed nucleation process. As a separate source of iron and oxygen is adopted, phase control could also be achieved by sequential injections of oxidizer.
Casula
Maria F
MF
Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, USA. casulat@unica.it
Jun
Young-Wook
YW
Zaziski
David J
DJ
Chan
Emory M
EM
Corrias
Anna
A
Alivisatos
A Paul
AP