Argonne National Laboratory Center for Nanoscale Materials U.S. Department of Energy

Superparamagnetic Gold Nanoshells with Tunable Optical Properties

Gold lNanoshells
Gold Nanoshells

TEM images showing the evolution of Au nanoshells after 12 cycles of seeded growth.;

A solution-phase process has been developed by CNM users from the University of California at Riverside, working collaboratively with the Nanophotonics Group, for synthesizing stable multifunctional colloidal particles composed of a superparamagnetic Fe3O4 core, a gold nanoshell, and a mesoporous silica outer layer. The unique porous silica layer is produced by a surface-protected etching process. By tuning the pore structure of the silica networks through etching, the shape and size of the gold nanoparticles can be controlled during the seeded growth, as well as their interparticle plasmon coupling. Controllable interparticle coupling enables “hot spots” for surface enhanced Raman scattering. The inclusion of responsive superparamagnetic Fe3O4 cores broadens the applications to include magnetically guided delivery and magnetic resonance imaging. The evolution from gold seeds to complete shells, and the corresponding change in plasmon bands, can be precisely controlled by the number of growth cycles and silica shell porosity.

Q. Zhang, J. Ge, J. Goebl, Y. Hu, Y. Sun, and Y. Yin, Adv. Mater., 22, 1905 (2010).
PhysOrg.com: http://www.physorg.com/news192821995.html

May 2010

U.S. Department of Energy Office of Science | UChicago Argonne LLC
Privacy & Security Notice | Contact Us | Site Map

The Center for Nanoscale Materials is an Office of Science User Facility operated for
the U.S.Department of Energy Office of Science by Argonne National Laboratory