Au@MoS₂@Au Hierarchical Nanostructures for High-Sensitivity and Recyclable SERS Device

The surface-enhanced Raman scattering (SERS) is widely used in chemical analysis and environmental monitoring. Herein, the Au@MoS₂@Au three core–shell hierarchical architecture is designed and synthesized through a hydrothermal method and spray process for a high-sensitivity Raman sensor. The enhanced Raman signals achieved in the hierarchical nanostructure are attributed to the two aspects. One is the local electromagnetic field from Au nanoparticles (NPs), including the surface satellites Au NPs and the core Au NPs, and the other is the chemical enhancement from MoS₂ nanosheets. As a result, a detection limit of the probe molecule (RhB) as low as 10⁻¹⁰ M is obtained via using this hierarchical Raman substrate. In addition, the hierarchical Au@MoS₂@Au Raman substrate can be recycled utilized because of MoS₂ photocatalytic ability. The unique Au@MoS₂@Au three core–shell nanostructure shows momentous potential to realize a SERS substrate with high-sensitivity and recyclable property.