Composite Structure Based on Gold-Nanoparticle Layer and HMM for Surface-Enhanced Raman Spectroscopy Analysis

Abstract

Hyperbolic metamaterials (HMMs), supporting surface plasmon polaritons (SPPs), and highly confined bulk plasmon polaritons (BPPs) possess promising potential for application as surface-enhanced Raman scattering (SERS) substrates. In the present study, a composite SERS substrate based on a multilayer HMM and gold-nanoparticle (Au-NP) layer was fabricated. A strong electromagnetic field was generated at the nanogaps of the Au NPs under the coupling between localized surface plasmon resonance (LSPR) and a BPP. Additionally, a simulation of the composite structure was assessed using COMSOL; the results complied with those achieved through experiments: the SERS performance was enhanced, while the enhancing rate was downregulated, with the extension of the HMM periods. Furthermore, this structure exhibited high detection performance. During the experiments, rhodamine 6G (R6G) and malachite green (MG) acted as the probe molecules, and the limits of detection of the SERS substrate reached 10−10 and 10−8 M for R6G and MG, respectively. Moreover, the composite structure demonstrated prominent reproducibility and stability. The mentioned promising results reveal that the composite structure could have extensive applications, such as in biosensors and food safety inspection.

Synthesis, Chemical–Physical Characterization, and Biomedical Applications of Functional Gold Nanoparticles: A Review

“…The interference of the molecules that contribute to adsorption can prevent the detection of target molecules. The plasmon band moves from the visible region for spherical AuNPs to the NIR by changing the size, shape, and level of aggregation [ 259 ].…”

Effective excitation of bulk plasmon-polaritons in hyperbolic metamaterials for high-sensitivity refractive index sensing

“…Second, the MHMM is an excellent sensing platform capable of coupling with other plasmon resonances to generate novel phenomena. Recently, it has been reported that the modification of nanoparticles on a MHMM acting as a 2D grating enabled the coupling of BPP and LSPR to generate an extremely strong electric field between the nanoparticles, 48,49 which is very useful for biomolecular detection.…”

Enhancement of Self-Collimation Effect in Photonic Crystal Membranes Using Hyperbolic Metamaterials

“…Usually, they exhibit average effects of the electromagnetic response of the medium. One branch of metamaterials is hyperbolic metamaterials (HMMs), which comprise layered metal-dielectric structures [ 17 , 18 , 19 , 20 ]. HMMs can show high anisotropic properties, owing to the presence of the opposite components of effective electric tensors.…”