surface-enhanced raman scattering (sers) christopher winta
TRANSCRIPT
![Page 1: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/1.jpg)
Surface-Enhanced Raman Scattering
(SERS)Christopher Winta
![Page 2: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/2.jpg)
1 Introduction
• SERS offers an improvement over normal Raman scattering in terms of sensitivity
• gives Raman enhancements of up to 106
![Page 3: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/3.jpg)
1 Introduction• 1974: initially observed by M. Fleischmann et
al. [1]
• 1977: Jeanmaire and Van Duyne: Enhancement can‘t be solely due to increased surface area
• 1978: M. Moskovits proposes electromagnetic theory
![Page 4: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/4.jpg)
2 Theory
• Roughness, periodic structure resonance frequency⇒
• Model roughness features with a sphere
![Page 5: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/5.jpg)
2 Theory𝐸𝑟=𝐸0 ∙cos𝜃+𝑔 (𝑎3𝑟3 )𝐸0 ∙cos𝜃
with
• Metal particle is surrounded by electric field with maximum at for .
• Enhancement of incident light
[2]
![Page 6: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/6.jpg)
2 Theory• Raman scattered light:
• gets enhanced by the surface plasmon: ⇒
• Measurement of intensity : for ⇒
![Page 7: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/7.jpg)
3 SERS in between particles
• Electric field in between particles increases as the distance decreases.
[2]
![Page 8: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/8.jpg)
3 SERS in between particles
[3]
![Page 9: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/9.jpg)
3 SERS in between particles[3]
![Page 10: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/10.jpg)
3 SERS in between particles[3]
![Page 11: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/11.jpg)
Thank you!
![Page 12: Surface-Enhanced Raman Scattering (SERS) Christopher Winta](https://reader035.vdocuments.net/reader035/viewer/2022062421/56649dbe5503460f94ab0c82/html5/thumbnails/12.jpg)
References1. M. Fleischmann, P.J. Hendra, A.J. McQuillan, Raman spectra of pyridine adsorbed at a silver electrode,
19742. Katrin Kneipp, Martin Moskovits, Harald Kneipp: Surface-Enhanced Raman Scattering: a Brief
Perspective, Springer, 20063. Hongxing Xu, Mikael Käll, Polarization-Dependent Surface-Enhanced Raman Spectroscopy of Isolated
Silver Nanoaggregates, 2003