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Author Spotlight: Tracking Electrochemistry on Single Nanoparticles with Surface-Enhanced Raman Scattering Spectroscopy and Microscopy
Published on: May 12, 2023
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Supercritical angle Raman microscopy: a surface-sensitive nanoscale technique without field enhancement
Diana Serrano1, Stefan Seeger1
1Department of Chemistry, University of Zurich, Wintherthurerstrasse 190, CH-8057 Zurich, Switzerland.
Light, Science & Applications
|September 1, 2018
Summary
Supercritical angle Raman (SAR) microscopy enables label-free, nanometre-resolution imaging of surfaces. This technique selectively collects Raman signals above the critical angle, enhancing surface specificity and signal-to-background ratios for molecular analysis.
Area of Science:
- Spectroscopy
- Microscopy
- Surface Science
Background:
- Raman scattering microscopy offers label-free molecular fingerprinting.
- Existing methods face challenges in achieving high resolution and signal specificity for surface analysis.
Purpose of the Study:
- To demonstrate a novel approach for surface-confined spontaneous Raman investigations.
- To achieve nanometre resolution and improved signal-to-background ratios for surface molecular analysis.
Main Methods:
- Selective collection of Raman scattered signals exceeding the critical angle for total internal reflection.
- Utilizing supercritical angle Raman (SAR) collection path.
- Comparison with parallel far-field collection path.
Main Results:
- Achieved nanometre resolution for surface-confined Raman investigations.
- Demonstrated significantly improved signal-to-background ratios due to high axial selectivity.
- Validated the richness of spectroscopic information from SAR collection.
Conclusions:
- Supercritical angle Raman (SAR) microscopy is a powerful tool for surface-related molecular specimens.
- The SAR technique offers enhanced specificity and resolution for label-free surface imaging.
- SAR microscopy can be used independently or combined with amplified Raman techniques.
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