Summary: Journal of Nanoparticle Research 1: 127­130, 1999.
© 1999 Kluwer Academic Publishers. Printed in the Netherlands.
Brief communication
Nanocomposite mullite/mullite powders by spray pyrolysis
Daniel M. Dabbs1,2
, Nan Yao2
and Ilhan A. Aksay1,2
1
Department of Chemical Engineering and 2
Princeton Materials Institute, Princeton University,
Princeton, NJ 08544, USA
Received 20 December 1998; accepted 30 December 1998
Key words: mullite, nanocomposite powder, coherent interface, phase transition
Abstract
A mullite/mullite nanocomposite powder has been synthesized, composed of nanometer-size 3Al2O3 · 2SiO2 (`3 : 2')
mullite precipitates within a matrix of the high alumina 2Al2O3 · SiO2 (`2 : 1') mullite. Historically, the transition
from the metastable high-alumina phase to the thermodynamically stable `3 : 2' phase of mullite has been thought
to be a continuous process, involving a continuous solid solution between the two forms of mullite. In contradiction
to this widely held view, our high resolution transmission electron microscopic characterization confirms that a first
order phase transition between two distinct mullites occurs. The high degree of interface coherence between the

Source: Aksay, Ilhan A. - Department of Chemical Engineering, Princeton University

Collections: Materials Science