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arXiv · 2606.27367

Accessing both electrochemical SEIRA and SERS with ultrasensitive metamaterials for enhanced molecular identification

Nicolas Spiesshofer·Tabitha Jones·Sarah May Sibug Torres·Zoltan Sztranyovszky·Caleb Todd·Shijie Zhu·Yeeun Roh·Rakesh Arul·Alexander Squires·Ivana Qianqi Lin·Angela Demtriadou·David O. Scanlon·Viv Lindo·Jeremy J. Baumberg
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Abstract

Surface-enhanced IR absorption (SEIRA) and surface-enhanced Raman spectroscopy (SERS) are complementary techniques that allow for ultrasensitive chemical fingerprinting. Non-invasive optical sensing would be significantly improved by a robust implementation of a reusable substrate that combines these techniques. Here, we present an electrochemically-cleanable metamaterial that enables combined real-time SEIRA and SERS in flow. This metamaterial facilitates the study of surface-adsorbed species and diffusion layers, elicits spectral shifts from changes in nanogap refractive index of 1400 nm/RIU, and delivers ultrasensitive analyte detection. Combining SERS and SEIRA clarifies molecular (electro)chemical transformations and tracks changes in selection rules and symmetry breaking at the analyte-electrode interface. This development in enhanced multimodal spectro-electrochemistry is suited for multiple domains, including understanding charge transport mechanisms and interfacial dynamics at electrodes, and is capable of real-time flow monitoring for a wide range of molecular processes.

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Nicolas Spiesshofer, Tabitha Jones, Sarah May Sibug Torres, Zoltan Sztranyovszky, Caleb Todd, Shijie Zhu, Yeeun Roh, Rakesh Arul, Alexander Squires, Ivana Qianqi Lin, Angela Demtriadou, David O. Scanlon, Viv Lindo, Jeremy J. Baumberg. 2026-06-25. Accessing both electrochemical SEIRA and SERS with ultrasensitive metamaterials for enhanced molecular identification. https://arxiv.org/abs/2606.27367

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