Robust SERS enhancement factor statistics using rotational correlation spectroscopy.
Nano Lett
; 12(6): 2912-7, 2012 Jun 13.
Article
em En
| MEDLINE
| ID: mdl-22551121
ABSTRACT
We characterize the distribution of surface-enhanced Raman spectroscopy (SERS) enhancement factors observed in individual hot spots of single Ag "nanocapsules", encapsulated Ag nanoparticle dimers formed via controlled nanoparticle linking, polymer encapsulation, and small molecule infusion. The enhancement factors are calculated for over 1000 individual nanocapsules by comparing Raman scattering intensities of 4-mercaptobenzoic acid (MBA) measured from single SERS hot spots to intensities measured from high-concentration solutions of MBA. Correlation spectroscopy measurements of the rotational diffusion identify nanocapsules with signals dominated by single hot spots via their strong polarization response. Averaging over the entire surface of the nanocapsules, the distribution of enhancement factors is found to range from 10(6) to 10(8), with a mean of 6 × 10(6). Averaging only over nanoparticle junctions (where most SERS signals are expected) increases this average value to 10(8), with a range from 2 × 10(7) to 2 × 10(9). This significant statistical sampling shows that very high SERS enhancement factors can be obtained on a consistent basis using nanoparticle linking.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Análise Espectral
/
Modelos Estatísticos
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Ressonância de Plasmônio de Superfície
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Nanoestruturas
Tipo de estudo:
Prognostic_studies
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Risk_factors_studies
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article