Layer-controlled large area MoS2 layers grown on mica substrate for surface-enhanced Raman scattering

Xu, Yuanyuan; Yang, Cheng; Jiang, Shouzhen; Man, Baoyuan; Liu, M.; Chen, C.S.; Zhang, C.; Sun, Zhencui; Qiu, Hengwei; Li, H.S.; Feng, Dejun; Zhang, J.X.

doi:10.1016/j.apsusc.2015.10.032

Cited by 37 publications

(23 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Two‐dimensional layered transition metal dichalcogenides (TMDs) of the MX 2 molecular form (M = Mo, W, Bb, Ta, Ti, Re; X = S, Se, Te) have attracted a significant interest recently because of their unique photonic and optoelectronic properties . Very recently, several members of the TMDs family, especially MoS 2 with a visible‐range bandgap (1.9 eV and 1.2–1.4 eV for single‐ and multilayer MoS 2 ) approximately, have been shown to be applicable for SERS . Qiu et al synthesized MoS 2 on flat and Si‐pyramids substrate by thermally decomposing the precursor (NH 4 ) 2 MoS 4 .…”

Section: Introductionmentioning

confidence: 99%

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS₂ (WS₂) Nanodomes/Graphene van der Waals Heterostructure Substrates

Ghopry

Alamri

Goul

et al. 2019

Advanced Optical Materials

105

View full text Add to dashboard Cite

electromagnetic enhancement (EM) and chemical enhancement (CM). The EM involves the local electromagnetic field enhancement that is typically attributed to the localized surface plasmonic resonance (LSPR) of free charge carriers at the surface of the metal nanostructures induced by the incident light. The LSPR wavelength is determined primarily by the free charge carrier concentration of the metal with a minor effect of the dimension and shape of the metal nanostructures. Molecules positioned [2] close to the LSPR nanostructures experience an enhanced evanescent electromagnetic field as compared to the incident excitation. This EM enhancement directly depends on the morphology of the metal surface, the wavelength of the incident light, and the dielectric constant of the surrounding medium of the metal. The EM enhancement factor can reach over 10 8 to enable ultrasensitive SERS detection down to the single-molecule level. [4][5][6] The CM is induced by the charge transfer between the SERS substrate and molecule with an enhancement factor typically on the order of 10 1 to 10 3 . [7][8][9] The CM effect is dictated by the interface electronic structures between the analyte and substrate and can be optimized by selecting a substrate with favorable band alignment with the highestoccupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) at the interface where the analyte (or probe molecule) bond to the substrate. Thus, tuning of the substrate electronic structure is important to an enhanced CM effect. [10] This has prompted intensive research exploring graphene-based SERS substrates considering the unique 2D atomically flat surface with delocalized π bonds, chemical inertness, biological compatibility, superior electronic and photonic properties, and the intrinsic Fermi energy at ≈4.5 eV that is compatible, as well as tunable, for CM enhancement with a large number of probe molecules. [7,8,11,12] Therefore, graphene is an excellent SERS substrate primarily due to the CM effect with the adsorbed molecules and the enhancement factor is quantitatively affected by the alignment of the probe molecule electronic structure with the Fermi level of graphene. [3,8] The EM and CM enhancement factors may be combined by adding metal nanostructures on graphene. [7,13] Since the 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 (MoS 2 and WS 2 ) 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 −11 to 10 −12 m on 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 ...

show abstract

Section: Introductionmentioning

confidence: 99%

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS₂ (WS₂) Nanodomes/Graphene van der Waals Heterostructure Substrates

Ghopry

Alamri

Goul

et al. 2019

Advanced Optical Materials

105

View full text Add to dashboard Cite

show abstract

“…Until now, a variety of methods have been developed 13 – 16 to fabricate a few layers or monolayer MoS 2 , including mechanically exfoliation, liquid exfoliation, thermal decomposition and chemical vapour deposition (CVD). Among them, the CVD method has been demonstrated as a promising method in producing large continuous MoS 2 films 17 , thickness modulated MoS 2 films 18 , 19 , and even large-area and highly quality monolayer MoS 2 films 20 . In the CVD growth process, temperature, gas flow and substrate all play essential roles in determining the final film morphology, crystalline structure and quality of film.…”

Section: Introductionmentioning

confidence: 99%

“…In the CVD growth process, temperature, gas flow and substrate all play essential roles in determining the final film morphology, crystalline structure and quality of film. In the previous reports, the different substrates, such as amorphous SiO 2 /Si 18 , 21 , 22 , single-crystal mica 19 and sapphire 23 , were adopted in MoS 2 CVD growth. In these cases, the triangular MoS 2 films were mainly synthesized due to the little influence of substrates.…”

Section: Introductionmentioning

confidence: 99%

Effect of Substrate symmetry on the dendrite morphology of MoS2 Film synthesized by CVD

Min

Zhou

et al. 2017

Sci Rep

View full text Add to dashboard Cite

In van der Waals epitaxial growth, the substrate plays a particularly important role in the crystal morphology. Here, we synthesized MoS2 by chemical vapour deposition on silicon carbide (SiC). The obtained MoS2 dendritic crystals show six-fold symmetry, which are different from the conventional triangular shapes on SiO2 substrate and from those with three-fold symmetry on SrTiO3 substrate. Interestingly, these MoS2 dendritic crystals on SiC exhibit an average fractal dimension 1.76, which is slightly larger than the classical Diffusion-limited-Aggregation fractal dimension 1.66. The first principle calculation indicates that the six-fold symmetry of the dendritic MoS2 is determined by the lattice symmetry of SiC. To further demonstrating the substrate effect, we break the natural six-fold lattice symmetry of SiC (0001) into groove arrays through etching the substrate. And then we successfully synthesized cross-type dendritic crystal MoS2 with two-fold symmetry. Its average fractal dimension 1.83 is slightly larger than the fractal dimension 1.76 of the previous MoS2 dendrite with six-fold symmetry. In a word, the symmetry of SiC substrate determined the symmetry and the fractal dimension of the dendritic MoS2. This work provides one possibility of inducing the growth orientation of dendritic crystals through controlling the substrate surface symmetry artificially.

show abstract

“…However, the role of interface charge trap densities between MoS 2 and the probe molecule for enhancement of the Raman signal was demonstrated. Xu et al demonstrated distinct Raman enhancement for an R6G probe molecule at 611, 773, 1361, and 1645 cm −1 in the fingerprint region (Figure b,c). This confirmed both charge transfer and dipole interactions in the enhancement mechanism, and that the enhancement effect was consistent irrespective of MoS 2 layer thickness (number of layer ≤3).…”

Section: D‐transition Metal Chalcogenides For Sensingmentioning

confidence: 93%

Section: D‐transition Metal Chalcogenides For Sensingmentioning

confidence: 99%

Recent Advances in 2D Inorganic Nanomaterials for SERS Sensing

et al. 2019

View full text Add to dashboard Cite

Surface‐enhanced Raman spectroscopy is a powerful and sensitive analytical tool that has found application in chemical and biomolecule analysis and environmental monitoring. Since its discovery in the early 1970s, a variety of materials ranging from noble metals to nanostructured materials have been employed as surface enhanced Raman scattering (SERS) substrates. In recent years, 2D inorganic materials have found wide use in the development of SERS‐based chemical sensors owing to their unique thickness dependent physico‐chemical properties with enhanced chemical‐based charge‐transfer processes. Here, recent advances in the application of various 2D inorganic nanomaterials, including graphene, boron nitride, semiconducting metal oxides, and transition metal chalcogenides, in chemical detection via SERS are presented. The background of the SERS concept, including its basic theory and sensing mechanism, along with the salient features of different nanomaterials used as substrates in SERS, extending from monometallic nanoparticles to nanometal oxides, is comprehensively discussed. The importance of 2D inorganic nanomaterials in SERS enhancement, along with their application toward chemical detection, is explained in detail with suitable examples and illustrations. In conclusion, some guidelines are presented for the development of this promising field in the future.

show abstract

Layer-controlled large area MoS2 layers grown on mica substrate for surface-enhanced Raman scattering

Cited by 37 publications

References 23 publications

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS₂ (WS₂) Nanodomes/Graphene van der Waals Heterostructure Substrates

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS₂ (WS₂) Nanodomes/Graphene van der Waals Heterostructure Substrates

Effect of Substrate symmetry on the dendrite morphology of MoS2 Film synthesized by CVD

Recent Advances in 2D Inorganic Nanomaterials for SERS Sensing

Contact Info

Product

Resources

About

Layer-controlled large area MoS2 layers grown on mica substrate for surface-enhanced Raman scattering

Cited by 37 publications

References 23 publications

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS2 (WS2) Nanodomes/Graphene van der Waals Heterostructure Substrates

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS2 (WS2) Nanodomes/Graphene van der Waals Heterostructure Substrates

Effect of Substrate symmetry on the dendrite morphology of MoS2 Film synthesized by CVD

Recent Advances in 2D Inorganic Nanomaterials for SERS Sensing

Contact Info

Product

Resources

About

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS₂ (WS₂) Nanodomes/Graphene van der Waals Heterostructure Substrates

Extraordinary Sensitivity of Surface‐Enhanced Raman Spectroscopy of Molecules on MoS₂ (WS₂) Nanodomes/Graphene van der Waals Heterostructure Substrates