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Title: Plasmon-Tuned Particles for the Amplification of Surface-Enhanced Raman Scattering from Analytes
Inelastic scattering from molecules because of vibrational modes produces unique Raman shifts, allowing these analytes to be detected with high specificity. Because Raman scattering is weak, surface-enhanced Raman scattering (SERS) has been used as a label-free technique for the detection of a variety of analytes at low concentrations. Using simple solution-based colloidal processing techniques, we have fabricated gold-coated carbon-black nanoparticles that show enhanced Raman activity. By varying the fabrication conditions, we create particles of different surface morphologies, allowing control over the peak wavelength for localized surface plasmon resonance (LSPR). By matching the LSPR wavelength to the incident laser wavelength, we get the highest signal from two model analytes, 4-nitrobenzenethiol (4-NBT) and Congo Red (CR). Our straightforward room temperature solution-based approach for making tunable SERS-active particles expands the range of incident radiation wavelengths that can be used for the detection of analytes using Raman scattering.  more » « less
Award ID(s):
1919588
PAR ID:
10386703
Author(s) / Creator(s):
; ; ;
Editor(s):
Chen, Zan
Date Published:
Journal Name:
Langmuir
Volume:
38
ISSN:
0743-7463
Page Range / eLocation ID:
14345-14354
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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