Localized Plasmonic Reconstruction via Xenon Photoactivation for High-Sensitivity SERS Substrates

Abstract

Surface-enhanced Raman scattering (SERS) has established itself as a powerful analytical platform for ultrasensitive molecular detection. Yet, conventional photoactivation and thermal annealing processes typically require prolonged treatment times, ranging from tens to hundreds of minutes, thereby, limiting throughput and scalability. In this work, we demonstrate an ultrafast xenon (Xe) photoinduced activation technique that reduces the surface activation time of Ag-based SERS substrates to just six seconds. Each Xe flash delivers a broadband, high-energy pulse that induces localized plasmonic heating and rapid surface energy transfer, driving nanoscale atomic reconstruction and charge redistribution within the metallic layer. This process substantially increases the density of plasmonic "hot spots," resulting in an eightfold enhancement in Raman intensity relative to untreated substrates. Structural and optical analyses (XRD, SEM, and UV-Vis) confirm that Xe irradiation precisely tailors both surface morphology and electronic configuration without inducing thermal degradation. The resulting substrates exhibit excellent signal uniformity, reproducibility, and long-term ambient stability. This solvent-free, energy-efficient, and scalable Xe photoactivation process offers a transformative pathway for fabricating high-performance SERS platforms, paving the way toward real-time, on-site chemical and biosensing technologies.