Preparation of silver nanosheet-assembled film as a surface-enhanced Raman scattering substrate

Abstract

Abstract In this work, we demonstrate a simple method for the fabrication of silver (Ag) nanosheet-assembled film on aluminum (Al) foil based on the galvanic displacement reaction between Al and Ag+. In order to obtain Ag nanosheets with large area and high aggregation density, both F− and H+ ions were introduced into the reaction system to etch the barrier layer Al2O3 on Al foils and promote the increase of the number of Ag nuclei. Therefore, Ag nuclei grew into nanosheets with citrate ions as the shape control agent. By varying the reaction parameters, Ag nanosheet film was optimized for surface-enhanced Raman scattering (SERS) measurements. The Ag nanosheet film prepared by the presented method exhibit the advantages of controllable morphology, good SERS activity, and distribution in large area, which could be utilized as a promising SERS-active candidate substrate for analytical applications.