▎ 摘　　要

NOVELTY - A reagent comprises reagents (A,B). Reagent (A) is an aqueous solution of graphene/nano precious metal compound, and reagent (B) is a surfactant solution. USE - Reagent is used for detecting polycyclic aromatic hydrocarbons e.g. perylene, pyrene, anthracene and/or fluorene, in water (all claimed). ADVANTAGE - The reagent enables rapid and convenient detection of polycyclic aromatic hydrocarbons in a water body, with good data repeatability with respect to both single-component and multi-component detection of polycyclic aromatic hydrocarbons. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for usage method of reagent, which involves dispersing reagent (B) in polycyclic aromatic hydrocarbon solution, adding reagent (A) to the mixed solution and uniformly mixing, and finally carrying out Raman detection on a suitable amount of the mixed solution to obtain a polycyclic aromatic hydrocarbon surface-enhanced Raman scattering spectrum.