Home

Influence of capping groups on the synthesis of γ-Fe2O3 nanocrystals

Ming Yin; Amanda Willis; Franz Redl; Nicholas J. Turro; Stephen P. O'Brien

Title:
Influence of capping groups on the synthesis of γ-Fe2O3 nanocrystals
Author(s):
Yin, Ming
Willis, Amanda
Redl, Franz
Turro, Nicholas J.
O'Brien, Stephen P.
Date:
Type:
Articles
Department:
Chemistry
Volume:
19
Permanent URL:
Book/Journal Title:
Journal of Materials Research
Abstract:
Monodisperse and uniform γ-Fe_2O_3 (maghemite) nanocrystals of variable size were prepared by thermal decomposition of iron pentacarbonyl [Fe(CO)_5] in the presence of surfactants, following controlled oxidation with trimethylamine N-oxide as a mild oxidant. The influence of carboxylic acids with variable alkyl carbon chain lengths on the synthesis of γ-Fe_2O_3 nanocrystals was investigated. The effect of the molar ratios of surfactant to iron precursor was also studied. The nanocrystals were characterized by x-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD showed the particles were highly crystalline at the nanometer scale. The results showed that the size and shape of the nanocrystal is strongly influenced by the decomposition temperature of iron pentacarbonyl and closely related to the length of carbon chain of the capping groups and the molar ratio of surfactant to iron precursor. Following controlled evaporation from nonpolar solvents, self-assembly into two-dimensional arrays could be observed by TEM. It was also found that the distance between the nanocrystals in self-assembled structures matched the length of the capping molecules very well.
Subject(s):
Chemistry
Publisher DOI:
http://dx.doi.org/10.1557/JMR.2004.0157
Item views:
206
Metadata:
text | xml

In Partnership with the Center for Digital Research and Scholarship at Columbia University Libraries/Information Services | Terms of Use