Three-dimensional cavity structure-assisted gold nanoparticles for surface-enhanced Raman scattering applications

The effect of surface-enhanced Raman scattering (SERS) depends on the structure of the SERS substrate, and the combination of special substrate structure and Au/Ag nanoparticles is an effective means for SERS. In this study, the bottom funnel head flower-shaped collapse array structure with unique morphology is prepared by improved anodic aluminum oxide (AAO) method, and gold nanoparticle (AuNPs) layers are embedded in the structure to synthesize composite substrates for high-performance Raman signal enhancement. The experimental conditions such as anodic oxidation time, reaming time, gold plating time and annealing time are discussed in detail with 4-aminothiophenol (4-ATP) as probe molecule, the ultra-low concentration detection with molecular concentration of 10 −13  mol/L can be realized. At the same time, the concentration and signal intensity shows a good linear relationship, and the field enhancement factor is as high as 1.24 × 10 6 . The structure of the substrate shows high repeatability, high sensitivity and high uniformity, which has a broad application prospect in the plasma devices based on anodic alumina.