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Abstract 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 10−12mon the TMD nanodomes/graphene vdW heterostructure substrates using 532 nm Raman excitation, which is comparable to the best sensitivity reported so far using plasmonic metal nanostructures/graphene SERS substrates, and is more than three orders of magnitude higher than that on single‐layer TMD and graphene substrates. Density functional theory simulation reveals enhanced electric dipole moments and dipole–dipole interaction at the TMD/graphene vdW interface, yielding an effective means to facilitate an external electrostatic perturbation on the graphene surface and charge transfer. This not only promotes chemical enhancement on SERS, but also enables electromagnetic enhancement of SERS through the excitation of localized surface plasmonic resonance on the TMD nanodomes. This TMD nanodome/graphene vdW heterostructure is therefore promising for commercial applications in high‐performance optoelectronics and sensing.
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This content will become publicly available on May 19, 2026
Surface-enhanced Raman scattering on two-dimensional Nb2CTX MXene
MXenes have garnered significant attention for surface-enhanced Raman scattering (SERS) applications due to their exceptional electronic properties and remarkable hydrophilicity. However, niobium carbide (Nb2CTX), a notable member of the MXene family, has been underexplored for SERS applications. In this work, we present a comprehensive investigation of the SERS properties of Nb2CTx nanosheets, using methylene blue (MB) and crystal violet (CV) as probe molecules under laser excitations at 532 and 488 nm. The results revealed that the Raman enhancement of dye molecules on the Nb2CTx-based SERS substrate was determined by the interplay between laser energy and the probe molecule. The two orders of magnitude higher enhancement factor (EF) for MB (2.12 × 106) compared to CV (2.65 × 104) obtained using 532 nm laser excitation was attributed to a light-induced resonance charge transfer transition within the MB-Nb2CTX system. The distinctly different EF values for MB and CV suggest that SERS technology based on chemical mechanisms could enable selective molecular detection. Our results provide valuable insights into the SERS mechanism and contribute to the development of cost-effective and 2D MXene-based selective SERS substrates for molecular sensing applications.
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- Award ID(s):
- 2213443
- PAR ID:
- 10644335
- Publisher / Repository:
- AIP publishing
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 126
- Issue:
- 20
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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