Investigation of the synthesis, SERS performance and application in glucose sensing of hierarchical 3D silver nanostructures

In this paper, the synthesis, SERS performance and application in glucose sensing of hierarchical 3D Ag nanostructures (NSs) are reported. Large-scale Ag jujube-like architectures were produced via the galvanic reaction process in a mixed solution of trisodium citrate (TSC) and AgNO3 on Cu nanoparticles disproportioned from Cu2O membranes. X-ray diffraction, scanning electron microscopy, atomic force microscopy, high resolution transmission electron microscopy, and Raman spectroscopy have been utilized to characterize the as-prepared samples. It was found that the defects existed in the Ag crystals may play a significant role in the morphological formation of the building units of the self-assemblies. In addition, the optimum ratio of the Ag+ concentration to the TSC addition amount for preparing the desired Ag nanojujubes (NJs) was determined by studying the effects of the Ag+ concentration and the TSC addition on the morphology of the final products. The formation mechanism of the hierarchical 3D AgNJs was then discussed. Furthermore, in terms of sensitivity, reproducibility and stability, jujube-like hierarchical architectures constituted of Ag nanosheets with highly-roughened surfaces were proved to be promising for surface-enhanced Raman scattering (SERS) applications, which were further demonstrated in comparison with other AgNSs. It is also worth pointing out that jujube-like hierarchical Ag architectures performed well in glucose detection, which would have great potential in the biological and medical fields.