Galvanic replacement synthesis of silver dendrites-reduced graphene oxide composites and their surface-enhanced Raman scattering characteristics

A simple method was developed to synthesize Ag dendrites/reduced graphene oxide (AgD/RGO) composites based on the galvanic displacement method. AgNO<inf>3</inf> was used as the precursor for Ag dendrites and aluminum foils served as the sacrifice metal. The as-synthesized AgD/RGO composite was characterized by SEM, FTIR, UV-vis spectroscopy and Raman spectroscopy. The results showed that the graphene oxide was successfully incorporated into the Ag dendritic structure and was reduced during the galvanic displacement between Ag+ ions and the aluminum foil. XRD analysis revealed that the Ag formed in the composite was in the cubic phase. The surface-enhanced Raman scattering (SERS) property of the as synthesized AgD/RGO composite was evaluated using Rhodamine B as a probe. The composite deposited substrate exhibited a much higher SERS activity compared with substrates modified with Ag dendrites or GO, indicating that the AgD/RGO could potentially be used as a highly sensitive SERS substrate for molecule detecting applications