NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Tunable Optical Properties of Metal Nanoparticle Sol-Gel CompositesWe demonstrate that the linear and non-linear optical properties of sol-gels containing metal nanoparticles are highly tunable with porosity. Moreover, we extend the technique of immersion spectroscopy to inhomogeneous hosts, such as aerogels, and determine rigorous bounds for the average fractional composition of each component, i.e., the porosity of the aerogel, or equivalently, for these materials, the catalytic dispersion. Sol-gels containing noble metal nanoparticles were fabricated and a significant blue-shift in the surface plasmon resonance (SPR) was observed upon formation of an aerogel, as a result of the decrease in the dielectric constant of the matrix upon supercritical extraction of the solvent. However, as a result of chemical interface damping and aggregation this blue-shift does not strictly obey standard effective medium theories. Mitigation of these complications is achieved by avoiding the use of alcohol and by annealing the samples in a reducing atmosphere.
Document ID
20020020429
Document Type
Reprint (Version printed in journal)
Authors
Smith, David D. (NASA Marshall Space Flight Center Huntsville, AL United States)
Snow, Lanee A. (Alabama Univ. Huntsville, AL United States)
Sibille, Laurent (Universities Space Research Association Huntsville, AL United States)
Ignont, Erica (Alabama Univ. Huntsville, AL United States)
Date Acquired
August 20, 2013
Publication Date
January 1, 2001
Publication Information
Publication: Journal of Non-Crystalline Solids
Volume: 285
ISSN: 0022-3093
Subject Category
Optics
Distribution Limits
Public
Copyright
Other