Two‐dimensional transition metal dichalcogenides (TMDs)/graphene van der Waals (vdW) heterostructures integrate the superior light–solid interaction in TMDs and charge mobility in graphene, and therefore are promising for surface‐enhanced Raman spectroscopy (SERS). Herein, a novel TMD (MoS2and WS2) nanodome/graphene vdW heterostructure SERS substrate, on which an extraordinary SERS sensitivity is achieved, is reported. Using fluorescent Rhodamine 6G (R6G) as probe molecules, the SERS sensitivity is in the range of 10−11to 10−12
Surface‐enhanced Raman spectroscopy (SERS) has become a sensitive detection technique for biochemical analysis. Despite significant research efforts, most SERS substrates consisting of single‐resonant plasmonic nanostructures on the planar surface suffer from limitations of narrowband SERS operation and unoptimized nano‐bio interface with living cells. Here, it is reported that nanolaminate plasmonic nanocavities on 3D vertical nanopillar arrays can support a broadband SERS operation with large enhancement factors (>106) under laser excitations at 532, 633, and 785 nm. The multi‐band Raman mapping measurements show that nanolaminate plasmonic nanocavities on vertical nanopillar arrays exhibit broadband uniform SERS performance with diffraction‐limited resolution at a single nanopillar footprint. By selective exposure of embedded plasmonic hotspots in individual metal–insulator–metal (MIM) nanogaps, nanoscale broadband SERS operation at the single MIM nanocavity level with visible and near‐infrared (vis–NIR) excitations is demonstrated. Numerical studies reveal that nanolaminate plasmonic nanocavities on vertical nanopillars can support multiple hybridized plasmonic modes to concentrate optical fields across a broadband wavelength range from 500 to 900 nm at the nanoscale.
more » « less- NSF-PAR ID:
- 10369482
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 32
- Issue:
- 32
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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