Noble metal modified ReS nanocavity for surface-enhanced Raman spectroscopy (SERS) analysis.

The rhenium disulphide (ReS) nanocavity-based surface enhanced Raman scattering (SERS) substrates ware fabricated on the gold-modified silicon pyramid (PSi) by thermal evaporation technology and hydrothermal method. In this work, the ReS nanocavity was firstly combined with metal nanostructures in order to improve the SERS properties of ReS materials, and the SERS response of the composite structure exhibits excellent performance in sensitivity, uniformity and repeatability. Numerical simulation reveals the synergistic effect of the ReS nanocavity and the plasmon resonance generated by the metal nanostructures. And the charge transfer between the metal, ReS and the analytes was also verified and plays an non-ignorable role. Besides, the plasmon-driven reaction for p-nitrothiophenol (PNTP) to p,p'-dimercaptobenzene (DMAB) conversion was successfully in-situ monitored. Most importantly, it is found for the first time that the SERS properties of ReS nanocavity-based substrates are strongly temperature dependent, and the SERS effect achieves the best performance at 45 °C. In addition, the low concentration detection of malachite green (MG) and crystal violet (CV) molecules in lake water shows its development potential in practical application.