A gold–silver nanostar 2D array composite structure for rapid SERS determination of PAHs

This study developed a portable multi-ring aromatic hydrocarbon (PAH) detection tool using a dual-metal surface-enhanced Raman scattering (SERS) substrate. Gold-silver nanostars (AuNS@Ag) were synthesized by a secondary seed-mediated growth method and assembled into a two-dimensional array by a liquid-phase interface self-assembly method, uniformly deposited on a silicon wafer. The PAHs in water samples were identified using a portable Raman spectrometer. The SERS detection platform has high sensitivity and stability, and can detect pyrene and phenanthrene with concentrations of 10-8 M and 0.5 × 10^-8 M, respectively. The stable dual-metal nanomaterial AuNS@Ag 2D array has potential application prospects and can be used for environmental monitoring.