Diatoms are single‐celled algae that biologically fabricate nanostructured silica shells with ordered pore arrays called frustules that resemble a 2D photonic crystal. A monolayer of
Quantitative Surface-Enhanced Spectroscopy
Surface-enhanced Raman scattering (SERS), a powerful technique for trace molecular detection, depends on chemical and electromagnetic enhancements. While recent advances in instrumentation and substrate design have expanded the utility, reproducibility, and quantitative capabilities of SERS, some challenges persist. In this review, advances in quantitative SERS detection are discussed as they relate to intermolecular interactions, surface selection rules, and target molecule solubility and accessibility. After a brief introduction to Raman scattering and SERS, impacts of surface selection rules and enhancement mechanisms are discussed as they relate to the observation of activation and deactivation of normal Raman modes in SERS. Next, experimental conditions that can be used to tune molecular affinity to and density near SERS substrates are summarized and considered while tuning these parameters is conveyed. Finally, successful examples of quantitative SERS detection are discussed, and future opportunities are outlined.
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- Award ID(s):
- 1707859
- PAR ID:
- 10337129
- Date Published:
- Journal Name:
- Annual Review of Physical Chemistry
- Volume:
- 73
- Issue:
- 1
- ISSN:
- 0066-426X
- Page Range / eLocation ID:
- 141 to 162
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Surface-enhanced Raman scattering (SERS) provides orders of magnitude of enhancements to weak Raman scattering. The improved sensitivity and chemical information conveyed in the spectral signatures make SERS a valuable analysis technique. Most of SERS enhancements come from the electromagnetic enhancement mechanism, and changes in spectral signatures are usually attributed to the chemical enhancement mechanism. As the electromagnetic mechanism has been well studied, we will give an overview of models related to the chemical mechanism, which explain the Raman response in terms of electronic transitions or induced electron densities. In the first class of models based on electronic transitions, chemical enhancements are attributed to changes in transitions of the molecule and new charge transfer transitions. The second class of models relate chemical enhancements to charge flows near the molecule–metal interface by partitioning the induced electron density of the SERS system in real space. Selected examples will be given to illustrate the two classes of models, and connections between the models are demonstrated for prototypical SERS systems.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1146/annurev-physchem-082720-033751
