Influence of the Local Environment on Determining Aspect-Ratio Distributions of Gold Nanorods in Solution Using Gans Theory
2007 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 111, 14299- p.Article in journal (Refereed) Published
We apply Gans theory to fit the absorption spectra of gold nanorods with aspect ratios R < 2.5 in solution using both the longitudinal and transversal surface plasmon resonance absorption peaks and the dielectric constant of the medium as a fitting parameter. By fitting the broadened absorption peaks using the absorption spectra of a set of nanorods with a range of aspect ratios, we determine the size distribution of the nanorods in solution. The optimum value of dielectric constant is substantially higher than the dielectric constant of the solvent, which is most likely due to a change in the effective dielectric constant in the vicinity of the nanorods. The validity of our method is confirmed by comparing the calculated size distributions with transmission electron microscope images, and we obtain a good agreement between the experiments and our calculations. Furthermore, several other recent experimental results are compared with our fitting method, and we find that the discrepancy between Gans theory and those experimental results can be explained by using higher values of dielectric constant.
Place, publisher, year, edition, pages
American Chemical Society (ACS), 2007. Vol. 111, 14299- p.
OPTICAL-ABSORPTION SPECTRA, MEDIUM DIELECTRIC-CONSTANT, SURFACE-PLASMON RESONANCE, METAL NANOPARTICLES, RAMAN-SCATTERING, GROWTH, SIMULATION, SILVER, SHAPE
IdentifiersURN: urn:nbn:se:kth:diva-48925DOI: 10.1021/jp074500rISI: 000249838300006OAI: oai:DiVA.org:kth-48925DiVA: diva2:458872
QC 201112072011-12-072011-11-242011-12-08Bibliographically approved