Espalhamento Raman intensificado pela superfície (SERS) no regime de detecção de uma molécula

Abstract

simulations in simple models of "hot spots" formed by Au nanorods.

Present and Future of Surface-Enhanced Raman Scattering

“…The electric fields in SERS hotspots are tightly localized and occupy a relatively small fraction of the surface area illuminated by the excitation laser. , When the surface concentration is also small, then the probability of molecules to be found in a hotspot becomes low, leading to strong variations (spatial and temporal) of the SERS signal, which, at the limit, can be assigned to SMs visiting the SERS hotspot. Figure shows an example of an experimental time-dependent trajectory of SIFs for R6G adsorbed on a nanostructured silver surface . The inset in Figure shows 5000 spectra acquired at every second.…”

“…The spectral data set is shown in the inset. Excitation was at 633 nm, and acquisition time was 1 s. Adapted with permission from ref . Copyright 2013 D. P. dos Santos.…”

“…Figure 28 shows an example of an experimental time-dependent trajectory of SIFs for R6G adsorbed on a nanostructured silver surface. 497 The inset in Figure 28 shows 5000 spectra acquired at every second. The "SERS intensity" from each spectrum was used to generate the temporal trajectory.…”

Estudo de compósito formado por nanopartículas de ouro em matriz polimérica como substratos para análise SERS.

“…A formação deste sistema permite a ocorrência de transferências de carga entre o HOMO (Highest Occupied Molecular Orbital) ou o LUMO (Lowest Unoccupied Molecular Orbital) da molécula e o nível de Fermi do metal [52][53][54]. Neste modelo, é considerado que o nível de Fermi do metal se situa entre os orbitais HOMO e o LUMO do analito, assim a transferência de carga pode ocorrer tanto no sentido metal→molécula quanto molécula→metal, dependendo da natureza da molécula [47,55].…”