Surface-Enhanced Raman Spectroscopy Substrates Using Nanostructured Materials

Surface-enhanced Raman spectroscopy (SERS) harnesses the amplification of inelastic light scattering by molecules in close proximity to plasmonic nanostructures, enabling the detection of chemical and biological species down to single-molecule levels. Central to its performance are engineered substrates composed of noble metals—typically silver or gold—structured at the nanoscale to generate intense electromagnetic “hot spots”. Nanofabrication techniques such as glancing angle deposition, chemical synthesis and lithography-free approaches yield a variety of architectures—including nanopillars, nanorods, nanohelices and sculptured thin films—that optimise field localisation and reproducibility. Recent advances have focused on scalable, low-cost methods to produce uniform, robust substrates and on understanding degradation mechanisms that limit long-term stability. These developments are unlocking practical applications in environmental monitoring, point-of-care diagnostics and on-site forensic analysis, while addressing challenges of signal reproducibility and substrate reusability.

Research from Nature Portfolio

Recent studies have elucidated fundamental stability issues of silver nanorod-based SERS substrates. One investigation revealed that ambient exposure leads to the adsorption of sulfur species and hydrocarbons on silver nanorods, causing a ~20 % drop in enhancement over three weeks before reaching a stable baseline. This work provides critical insight into storage protocols and surface passivation strategies to maintain signal fidelity. Ongoing efforts are exploring surface coatings and alloying to mitigate such degradation without compromising hot-spot density.

Research from all publishers

Innovative lithography-free fabrication of three-dimensional silver and gold nanopillars via rapid glancing angle deposition has demonstrated reliable detection limits as low as 10–18 M for model analytes. These scalable substrates, combined with portable Raman spectrometers, enable on-site diagnostics outside traditional laboratory settings. A comprehensive review of silver nanostructured platforms highlights progress in physical vapour deposition, chemical synthesis and optical-fibre-based assemblies, detailing how tuneable plasmon resonances and particle morphologies influence SERS and SPR performance. Another review on sculptured thin films prepared by glancing angle deposition summarises how control of tilt angle, rotation and deposition parameters yields highly uniform nanocolumns that overcome brittleness, adhesion and signal inhomogeneity, paving the way for reusable, large-area SERS substrates.

Surface-Enhanced Raman Spectroscopy Substrates Using Nanostructured Materials publication trend

The graph below shows the total number of articles in surface-enhanced raman spectroscopy substrates using nanostructured materials across all publications each year (not limited to Nature Index journals).

Technical terms

Surface-enhanced Raman spectroscopy (SERS): A technique that increases Raman signal intensity by orders of magnitude through the interaction of molecules with plasmonic nanostructures.

Localized surface plasmon resonance (LSPR): The collective oscillation of conduction electrons in metallic nanostructures excited by incident light at specific wavelengths, leading to intense local electromagnetic fields.

Hot spot: A nanoscale region near metal nanostructures where the electromagnetic field is exceptionally amplified, driving enhanced Raman scattering.

Glancing angle deposition (GLAD): A physical vapour deposition method in which the vapour flux arrives at an oblique angle to the substrate normal, promoting self-shadowing and the growth of tilted or helical nanostructures.

Nanostructured substrate: A supporting material engineered with features at the nanometre scale to manipulate light–matter interactions and enhance spectroscopic signals.

References

1. Lithography-free fabrication of scalable 3D nanopillars as ultrasensitive SERS substrates. Applied Materials Today (2023).
2. Recent Advances in Silver Nanostructured Substrates for Plasmonic Sensors. Biosensors (2022).
3. Sculptured thin films: Overcoming the limitations of surface-enhanced Raman scattering substrates. Applied Surface Science Advances (2022).
4. Degradation Mechanism of Ag Nanorods for Surface Enhanced Raman Spectroscopy. Scientific Reports (2017).