Preparation of the Surface-Enhanced Raman Composite Substrate GO@PVA@Pd@Ag and Study on the Detection of Phenanthrene and Pyrene in Aqueous Solution

In this paper, a surface-enhanced Raman scattering (SERS)-active substrate of GO@PVA@Pd@Ag was fabricated via a composite loading method. Palladium-silver (Pd@Ag) bimetallic nanoparticles were employed as the core enhancement unit, graphene oxide (GO) served as the carrier, and polyvinyl alcohol (PVA) functioned as the dispersant and stabilizer. The structure and properties of the substrate were analyzed by diverse characterization methods, including BET, Fourier transform infrared spectrometry (FTIR), Scanning Electron Microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Subsequently, the SERS enhancement mechanism was preliminarily discussed. The prepared SERS-active substrate was employed to detect phenanthrene and pyrene in aqueous solution, with detection limits of 10−7 g/L and 10−8 g/L. In comparison with conventional Raman spectroscopy, this approach substantially reduces the detection limit and is anticipated to be utilized for the rapid detection of trace phenanthrene in the environment.