Abstract
In this work, we designed and prepared a hierarchically assembled 3D plasmonic metal-dielectric-metal (PMDM) hybrid nano-architecture for high-performance surface-enhanced Raman scattering (SERS) sensing. The fabrication of the PMDM hybrid nanostructure was achieved by the thermal evaporation of Au film followed by thermal dewetting and the atomic layer deposition (ALD) of the Al2O3 dielectric layer, which is crucial for creating numerous nanogaps between the core Au and the out-layered Au nanoparticles (NPs). The PMDM hybrid nanostructures exhibited strong SERS signals originating from highly enhanced electromagnetic (EM) hot spots at the 3 nm Al2O3 layer serving as the nanogap spacer, as confirmed by the finite-difference time-domain (FDTD) simulation. The PMDM SERS substrate achieved an outstanding SERS performance, including a high sensitivity (enhancement factor, EF of 1.3 × 108 and low detection limit 10−11 M) and excellent reproducibility (relative standard deviation (RSD) < 7.5%) for rhodamine 6G (R6G). This study opens a promising route for constructing multilayered plasmonic structures with abundant EM hotspots for the highly sensitive, rapid, and reproducible detection of biomolecules.
Highlights
In this work, we designed and prepared a hierarchically assembled 3D plasmonic metaldielectric-metal (PMDM) hybrid nano-architecture for high-performance surface-enhanced Raman scattering (SERS) sensing
The SERS enhancement mostly relies on the amplification of the electromagnetic field—i.e., electromagnetic (EM) hot spots generated by the excitation of the localized surface plasmon resonance (LSPR) of the metal nanostructures [17]
Inspired by the above discussion, we report a facile method for fabricating abundant nanogaps containing hierarchically assembled 3D plasmonic metal-dielectric-metal (PMDM) hybrid nano-architectures for superior SERS detection in this work
Summary
We designed and prepared a hierarchically assembled 3D plasmonic metaldielectric-metal (PMDM) hybrid nano-architecture for high-performance surface-enhanced Raman scattering (SERS) sensing. Owing to its extremely high sensitivity, ability to work in real time, and multiplexing detection capability, surface-enhanced Raman scattering (SERS) has emerged as a powerful detection technique for sensing molecules through its unique fingerprint vibrational spectrum [1,2,3,4,5]. It has tremendous potential for single-molecule level detection [6,7], the investigation of live cells [8,9], the monitoring of catalytic reactions [10,11], and sensing molecules, in both liquid and solid samples [12,13]. Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
