Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 5 November 2004:
Vol. 306. no. 5698, pp. 1009 - 1012
DOI: 10.1126/science.1103755
Prev | Table of Contents | Next

Reports

Cation Exchange Reactions in Ionic Nanocrystals

Dong Hee Son,1 Steven M. Hughes,2 Yadong Yin,1 A. Paul Alivisatos1,2*

Cation exchange has been investigated in a wide range of nanocrystals of varying composition, size, and shape. Complete and fully reversible exchange occurs, and the rates of the reactions are much faster than in bulk cation exchange processes. A critical size has been identified below which the shapes of complex nanocrystals evolve toward the equilibrium shape with lowest energy during the exchange reaction. Above the critical size, the anion sublattice remains intact and the basic shapes of the initial nanocrystals are retained throughout the cation exchange. The size-dependent shape change can also be used to infer features of the microscopic mechanism.

1 Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
2 Department of Chemistry, University of California, Berkeley, CA 94720, USA.

* To whom correspondence should be addressed. E-mail: alivis{at}berkeley.edu

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Doped Nanocrystals.
D. J. Norris, A. L. Efros, and S. C. Erwin (2008)
Science 319, 1776-1779
   Abstract »    Full Text »    PDF »
Spontaneous Superlattice Formation in Nanorods Through Partial Cation Exchange.
R. D. Robinson, B. Sadtler, D. O. Demchenko, C. K. Erdonmez, L.-W. Wang, and A. P. Alivisatos (2007)
Science 317, 355-358
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)