Ultrasensitive detection of a 1-pyrenecarboxylic acid by surface enhanced Raman scattering hot spot with reduced graphene oxide/silver nanoparticles composites

This manuscript demonstrated a simple and efficient method to detect 1-pyrenecarboxylic acid dissolved in water solution at nanoscale level via surface enhanced Raman scattering hot spot with reduced graphene oxide/silver nanoparticles (Ag-NPs) nanocomposites (RGO/Ag-NPs). Ag-NPs were attached in situ onto RGO surface with different concentrations of AgNO₃ in the presence of aqueous solution of 1-pyrenecarboxylic acid. The morphology and structures of the as-prepared samples were characterised with FT-IR, UV-vis absorption, DLS, Zeta potentials, Raman spectroscopy, TEM and XRD. At higher AgNO₃ concentration, Ag-NPs get aggregated onto the surface of RGO and created surface enhanced Raman spectroscopy (SERS) hot spot which detect 1-pyrenecarboxylic acid due to the greatly enhanced electromagnetic field. This novel concept can be extended for sensing different water pollutants including polycyclic aromatic hydrocarbons and benzene derivatives.