Using Tip-Enhanced Raman Spectroscopy in Nanoscale Chemical Analysis
Tip-enhanced Raman spectroscopy (TERS) employs localized surface plasmon resonance at the apex of a sharp scanning probe microscopy tip to overcome the diffraction limit inherent in conventional Raman spectroscopy, allowing researchers the ability to access spatial resolutions down to the nanometer scale. This technique has established itself as a powerful tool in nanoscale chemical analysis, delivering previously unachieved spatial resolution with superior molecular sensitivity and chemical specificity.
Researchers at the Department of Chemistry and Applied Biosciences at ETH Zurich, (Zurich, Switzerland) report that their recent studies demonstrate the unique capabilities of tip-enhanced Raman spectroscopy (TERS) for in situ monitoring of catalytic reactions, nanoscale mapping of phase behavior in biomembranes, and precise characterization of photovoltaic interfaces. A review paper based on their work, published in Chimia (1), highlights the potential of this technique for the addressing of critical challenges across the chemical, biological, and materials sciences. Their efforts serve as a guide for other researchers aiming to harness TERS for label-free, non-destructive nanoanalysis to advance the understanding of complex molecular materials and processes through ultrahigh sensitivity, specificity, and spatial resolution.
John Wessel initially proposed the concept of TERS in 1985 (3), and the technique was first experimentally demonstrated at ETH Zurich in 2000 (4), with the presenters leveraging theNobel Prize-winning invention of scanning tunneling microscopy (STM) at IBM Zurich (5). Three independent research groups also experimentally realized TERS through their experimentation that same year (6-8).
When conducting an experiment involving TERS, a silver or gold SPM tip is positioned in the focal spot of an excitation laser. When the laser frequency matches with the natural oscillation frequency of conduction electrons in the metal, this creates a localized surface plasmon resonance (LSPR) which heightens the electromagnetic field at the tipapex by several orders of magnitude; the strength is further amplified through the “lightning rod effect” (LRE), a non-resonant enhancement caused by the sharpness of the tip (1,9). TERScanbeperformedindifferentopticalgeometries,including top-, bottom-, side- and parabolic-illumination, with each format offering uniquedistinctadvantages (10-13).
The authors of the paper believe that the unique capability of TERS for nanoscale chemical imaging with ultrahigh sensitivity and chemical specificity offers great potential for driving advances across a variety of research areas within the physical, chemical, material, and biological science areas. They anticipate that the integration of TERS with many corresponding techniques, including high-speed or electrical-mode atomic force microscopy (AFM), electrochemical analysis, or nano-infrared (IR) spectroscopy, will continue to expand its possible uses, and provide deeper insights into complex molecular systems (1).
A laboratory with a setup for spectroscopic analysis. © Football- stock.adobe.com
References
1. Bienz, S.; Xu, C.; Xia, Y.; Dutta, A.; Zenobi, R.; Kumar, N. Advancements in Nanoscale Chemical Analysis Using Tip-Enhanced Raman Spectroscopy. Chimia (Aarau) 2025, 79 (1-2), 52–59. DOI: 10.2533/chimia.2025.52
2. Abbe, E. Beiträge zur Theorie des Mikroskops und der mikroskopischen Wahrnehmung. Archiv f. mikrosk. Anatomie 1873, 9, 413–468. DOI: 10.1007/bf02956173
3. Wessel, J. Surface-Enhanced Optical Microscopy. J. Opt. Soc. Am. B 1985,2, 1538–1541. DOI: 10.1364/josab.2.001538.
4. Stöckle, R. M.; Suh, Y. D.; Deckert, V.; Zenobi, R. Nanoscale Chemical Analysis by Tip-Enhanced Raman Spectroscopy. Chem. Phys. Lett. 2000,318, 131. DOI: 10.1016/S0009-2614(99)01451-7
5. Bining, G.; Rohrer, H. Scanning Tunneling Microscopy-From Birth to Adolescence. Rev. Mod. Phys. 1987, 59 (3), 615–625. DOI: 10.1103/RevModPhys.59.615
6. Anderson, M. S. Locally Enhanced Raman Spectroscopy with an Atomic Force Microscope. Appl. Phys. Lett. 2000, 76 (21), 3130–3132. DOI: 10.1063/1.126546
7. Hayazawa, N.; Inouye, Y.; Sekkat, Z.; Kawata, S. Metallized Tip Amplification of Near-Field Raman Scattering. Opt. Commun. 2000, 183 (1-4), 333–336. DOI: 10.1016/S0030-4018(00)00894-4
8. Pettinger, B.; Picardi, G.; Schuster, R.; Ertl, G. Surface Enhanced Raman Spectroscopy: Towards Single Molecule Spectroscopy. Electrochemistry 2000, 68 (12), 942–949. DOI: 10.5796/electrochemistry.68.942
9. Asghari‐Khiavi, M.; Wood, B. R.; Hojati‐Talemi, P.; Downes, A.; McNaughton, D.; Mechler, A. Exploring the Origin of Tip‐Enhanced Raman Scattering; Preparation of Efficient TERS Probes with High Yield. J. Raman Spectrosc. 2012, 43 (2), 173–180. DOI: 10.1002/jrs.3021
10. Yang, Z.;Aizpurua, J.; Xu, H. Electromagnetic Field Enhancement in TERS Configurations. J. Raman Spectrosc. 2009, 40 (10), 1343–1348. DOI: 10.1002/jrs.2429.
11. Mehtani, D.; Lee, N.; Hartschuh, R. D.; Kisliuk, A.; Foster, M. D.; Sokolov, A. P.; Maguire, J. F. Nano‐Raman Spectroscopy with Side‐Illumination Optics. J. Raman Spectrosc. 2005, 36 (11), 1068–1075. DOI: 10.1002/jrs.1409.
12. Deckert-Gaudig, T.; Richter, M.; Knebel, D.; Jähnke, T.; Jankowski, T.; Stock, E.; Deckert, V. A Modified Transmission Tip-Enhanced Raman Scattering (TERS) Setup Provides Access to Opaque Samples. Appl. Spectrosc. 2014, 68 (8), 916–919. DOI: 10.1366/13-07419.
13. Wang, X., Huang, S. C.; Huang, T. X.; Su, H. S.; Zhong, J. H.; Zeng, Z. C. et al. Tip-Enhanced Raman Spectroscopy for Surfaces and Interfaces. Chem. Soc. Rev. 2017, 46 (13), 4020–4041. DOI: 10.1039/C7CS00206H
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