Nanorod-coated PNIPAM microgels: Thermoresponsive optical properties

COLL 178

Matthias Karg, Matthias.Karg@tu-berlin.de1, Isabel Pastoriza-Santos, pastoriza@uvigo.es2, Jorge Pérez-Juste, juste@uvigo.es2, Thomas Hellweg, thomas.hellweg@tu-berlin.de3, and Luis M. Liz-Marzán, lmarzan@uvigo.es2. (1) Stranski Laboratory of Physical and Theoretical Chemistry, Technical University Berlin, Strasse des 17. Juni 124, 10623 Berlin, Germany, (2) Departamento de Quimica Fisica, Universidade de Vigo, Campus Universitario, 36310, Vigo, 36200, Spain, (3) Physical Chemistry I, University Bayreuth, Universitaetsstrasse 30, Bayreuth, 95440, Germany
Highly-charged, thermoresponsive poly-(N-isopropylacrylamide) microgels have been coated with polyelectrolyte-coated gold nanorods. The surface coverage of such hybrid particles was varied by changing the ratio of nanorods to microgel and determined from electron microscopy images. Temperature dependent UV-VIS measurements were done to investigate the optical behavior during the collapse of the microgel core. The results show that there appear red-shifts of the longitudinal plasmon band due to increasing electronic interactions between the gold nanorods when the polymer cores decrease in size. Further observed effects are an increase in the band width and a loss in intensity of the longitudinal band. These properties strongly depend on the surface coverage and are therefore tuneable, which makes them interesting for applications such as optical filters.
 

Fundamental Research in Colloid and Surface Chemistry
6:00 PM-8:00 PM, Monday, August 20, 2007 BCEC -- East Registration, Poster

Division of Colloid & Surface Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007