A new route for the synthesis of a Ag nanopore–inlay–nanogap structure: integrated Ag-core@graphene-shell@Ag-jacket nanoparticles for high-efficiency SERS detection

Abstract

We present a new route for the synthesis of Ag nanopore–inlay–nanogap structures using creviced graphene-shell encapsulated Cu nanoparticles (Cu@G-NPs) as the sacrificial templates. The as-synthesized integrated Ag-core@graphene-shell@Ag-jacket nanoparticles (AgC@G@AgJ-NPs) presents “chrysanthemum” shapes that contain abundant sub-10 nm size intraparticle nanopores/nanogaps, which can generate huge enhanced electromagnetic fields to support SERS activity, resulting in an average EF > 10⁷ due to a high-density of intraparticle and interparticle “hot spots”.