Artículos de revistas
Single-molecule Surface-enhanced (resonance) Raman Scattering (se(r)rs) As A Probe For Metal Colloid Aggregation State
Registro en:
Journal Of Physical Chemistry C. Amer Chemical Soc, v. 120, p. 20877 - 20885, 2016.
1932-7447
WOS:000384034600047
10.1021/acs.jpcc.6b02400
Autor
dos Santos
Diego P.; Temperini
Marcia L. A.; Brolo
Alexandre G.
Institución
Resumen
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Single-molecule surface-enhanced (resonance) Raman scattering (SM-SE(R)RS) studies have applications beyond analytical chemistry. For instance, SM-SERS spectra carry information about the molecule interaction with the hotspots (regions of strong electric field enhancement due to surface plasmon resonance). The analysis of the time- (or spatial-) dependent fluctuations in SM-SERS spectra permits, for instance, the study of resonance contributions from the local electric field to imbalances in the anti-Stokes to Stokes intensity ratios (I-AS/I-S). This analysis is a tool for the characterization of the resonance energies of the hotspots. In the case of colloidal samples, the structures of the hotspots and their properties are dependent upon the colloidal aggregation state. The analysis Of the I-AS/I-S ratios in such a system can be a useful characterization tool to infer the hotspot structures for different aggregation states. In this work, the distributions of I-AS/I-S ratio for crystal violet (CV) adsorbed in Ag colloids at different aggregation states was studied under SM-SERS conditions. The experimental results were interpreted in terms of the generalized Mie theory (GMT) simulations. 120 37 20877 20885 FAPESP (Brazil) NSERC (Canada) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)