▎ 摘　　要

NOVELTY - Composite surface enhanced Raman spectroscopy (SERS) substrate of silver nanowire-graphene-gold nanosphere comprises substrate; silver nanowire layer coated on substrate; and gold nanosphere layer located at uppermost layer. The graphene film and thiol are coated between silver nano-sphere layer and gold nanosphere layer. The coverage rate of silver nanosphere layer on substrate is 60-80%; and adhesion rate of gold nano-sphere layer to graphene film is 50-70%. USE - Composite SERS substrate of silver nanowire-graphene-gold nanosphere used for detecting polycyclic aromatic hydrocarbon and organic pollutant. ADVANTAGE - The composite SERS substrate is easy to prepare; and adopt high detection accuracy. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a a method for preparing composite SERS substrate of silver nanowire-graphene-gold nanosphere, which involves: (a) synthesizing silver nanowire ethanol sol and gold nanosphere hydrosol; (b) dropping silver nanowire ethanol preset concentration on glass sheet under preset temperature, volatilizing solution to form three-dimensional silver nanowire net-shaped structure; (c) coating graphene solution with preset concentration to surface of silver nanowire net-shaped structure by spin coating instrument, after volatilizing solution, forming silver nanowire-graphene structure; (d) placing nanowire-graphene structure in mercaptan solution with preset concentration for pre-set time and taking out, dropping polycyclic aromatic hydrocarbon ethanol surface of silver nanowire-graphene; (e) placing silver nanowire-graphene structure on preset temperature hot plate until solution volatilized; and (f) dropping gold nanosphere hydrosol with preset concentration to surface of silver nanowire-graphene structure, volatilizing solution to form composite SERS substrate of silver nanowire-graphene-gold nanosphere.