Intercalated 4-Aminobenzenethiol between Au and Ag Nanoparticles: Effects of Concentration and Nanoparticles Neighborhood on its SERS Response

Santos, Elias de Barros; Sígoli, Fernando Aparecido; Mazali, Ítalo Odone

doi:10.5935/0103-5053.20150060

Cited by 6 publications

(6 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, dissociation to the zwitterion form and/or binding to the metal significantly increase the absorption threshold wavelength, as can be seen in the absorption spectra plotted in Figure . The simulated absorption spectrum of ABT zw is in a good agreement with the experiment in ref . At present, we are not able to simulate the metal bulk on an atomic level.…”

Section: Results and Discussionsupporting

confidence: 83%

“…This could not be explained by accuracy of the DFT computations or by the effect of molecular orientation and was attributed to an uneven enhancement across a wider spectral region in the experiment. Indeed, the silver plasmonic resonance quickly diminishes beyond the 785 nm excitation, 39 which makes the measured signal of high-wavenumber vibrations smaller.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Explanation of Surface-Enhanced Raman Scattering Intensities of p-Aminobenzenethiol by Density Functional Computations

et al. 2016

View full text Add to dashboard Cite

p-Aminobenzenethiol (ABT) is a popular molecule for surfaceenhanced Raman scattering experiments (SERS), providing large signal enhancements on a range of metal surfaces. However, SERS intensities vary very much according to experimental conditions, and the interplay between ABT protonation, polymer state, and electronic structure/Raman cross section is still not completely clear. To understand main factors affecting Raman intensities, density functional theory (DFT) and matrix polarization theory (MPT) models were used to generate the spectra and compare to the experiment. The simulations showed that ABT protonation as well as its binding to the metal surface shift the absorption threshold, which invokes resonance or preresonance conditions favorable to the signal enhancement. The MPT approximation enabled modeling of the effect of the metal bulk and orientation of the dye on the metal surface on the enhancement and relative band intensities. The simulations can be done relatively easily and reveal chemical changes and system geometry important in rational design of SERS molecular sensors.

show abstract

Section: Results and Discussionsupporting

confidence: 83%

Section: ■ Results and Discussionmentioning

confidence: 99%

Explanation of Surface-Enhanced Raman Scattering Intensities of p-Aminobenzenethiol by Density Functional Computations

et al. 2016

View full text Add to dashboard Cite

show abstract

“…6,7 SERS and SEF have been developed over the years to be applied in several areas, such as analytical chemistry, [6][7][8][9] biodiagnostics, [10][11][12] and materials science. [13][14][15] One major issue for plasmon-enhanced spectroscopies is the observation that nanoparticles of coinage metals (Au, Ag and Cu) interact strongly with each other and may form aggregates in suspension, which strongly affects both suspension stability and spectroscopic characteristics reproducibility. In this context, the shellisolated nanoparticle (SHIN) substrates emerged aiming to minimize the aggregation effects.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of Au@MnO2 Nanoparticles as Plasmon Enhanced Spectroscopy Substrates

Oliveira¹,

Neves²,

Peixoto³

et al. 2023

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

The plasmonic properties of Au nanoparticles (AuNP), which allow the observation of enhanced spectroscopic effects, are strongly affected by the aggregation and precipitation caused by the strong interactions between nanoparticles. To avoid AuNP aggregation and precipitation, the present study proposes coating with MnO2, forming AuNP@MnO2 core-shell structures. The MnO2 layers presented 1-10 nm thickness so that highly surface-enhanced fluorescence was obtained with maximum intensity given by 5 nm thick MnO2. The decrease in Raman intensity could be controlled, despite the inherent reduction in surface-enhanced Raman scattering (SERS) intensity with increasing adsorbate-surface distance. The decrease in Raman intensity was compensated by increasing AuNP stability caused by the MnO2 shell.

show abstract

“…Surface-enhanced Raman spectroscopy (SERS) has emerged as one of the most versatile tools for sensing environmental control, biomedicine analysis, security, a criminal investigation, agriculture, among others. − This technique offers an enormous enhancement factor (as high as 10 10 to 10 14 orders) over traditional Raman signal intensity issues, with high sensitivity and capability of single-molecule detection (SMD). ,,, SERS-based molecular detection can be achieved using metallic nanostructures as plasmonic nanoantennas to amplify Raman signals, mostly using silver or gold nanoparticles in colloidal suspension or nanostructured metallic films. ,− The enhanced-Raman signal using metallic nanostructures is particularly strong at nanoscopically sharp corners, tips, and mainly in interparticle gaps called hot spots. In this sense, gold nanorods (AuNRs) have attracted extensive attention and scientific interest for SERS due to their anisotropic shape and the strong coupling with the electromagnetic field. ,− Briefly, the transverse and longitudinal plasmonic resonance bands (TPR and LPR, respectively) of AuNRs bring fascinating optical properties for SERS applications. ,, Even more exciting is the LPR wavelength position finely tuned from visible to near-infrared by adjusting the nanoparticle aspect ratio. ,,− It is a fundamental characteristic since the Raman intensity is strongly dependent on the nanoparticle aspect ratio with the magnitude of SERS enhancement crucially reliant on the assembly and organization of metallic nanoparticles to obtain reproducible signals.…”

Section: Introductionmentioning

confidence: 99%

Dynamic Behavior of Surface-Enhanced Raman Spectra for Rhodamine 6G Interacting with Gold Nanorods: Implication for Analyses under Wet versus Dry Conditions

Barros

Shimizu

Oliveira

et al. 2020

ACS Appl. Nano Mater.

Self Cite

View full text Add to dashboard Cite

We report the dynamic behavior of surface-enhancement Raman scattering (SERS) spectra using rhodamine 6G dye (R6G, 10–8 mol L–1) adsorbed on gold nanorods (AuNRs). SERS spectra displayed a strong time-dependence intensity in wet to dry transition states. FEG-SEM images reveal a stacking of AuNRs organization that can lead to Raman signal improvements due to the formation of a 3D hot spot matrix that acts as a trap for target molecules. AuNRs nanostructured films were efficiently employed to form SERS substrates. The independent random AuNR organization in the SERS spectra exhibits a characteristic profile of intensities due to different dielectric environmental conditions. Despite the variations observed in the spectra array, a pattern was recognized by statistical analysis. Multidimensional analysis ensured the distinction of the study’s requirements applied to the SERS response, exhibiting a silhouette coefficient of 0.92 with the least-squares projection technique. Changes in the SERS spectra profile from wet to dry state conditions of R6G dye solution can be interpreted as the dynamic behavior of R6G molecules correlated to distinct molecular adsorption and (or) surface distribution of the R6G molecules proving different plasmonic resonances. Simulations obtained from BEM calculation in experimental data corroborate that the SERS enhancement is strongly dependent on the nanoparticle coupling in nanoscale and the dielectric environment.

show abstract

Intercalated 4-Aminobenzenethiol between Au and Ag Nanoparticles: Effects of Concentration and Nanoparticles Neighborhood on its SERS Response

Cited by 6 publications

References 1 publication

Explanation of Surface-Enhanced Raman Scattering Intensities of p-Aminobenzenethiol by Density Functional Computations

Explanation of Surface-Enhanced Raman Scattering Intensities of p-Aminobenzenethiol by Density Functional Computations

Synthesis and Characterization of Au@MnO2 Nanoparticles as Plasmon Enhanced Spectroscopy Substrates

Dynamic Behavior of Surface-Enhanced Raman Spectra for Rhodamine 6G Interacting with Gold Nanorods: Implication for Analyses under Wet versus Dry Conditions

Contact Info

Product

Resources

About