(a) The Raman scattering spectrum of monolayer WS2excited by a 532 nm laser line. The asterisks denote the second-order Raman phonon modes. (b) The Raman mapping of thepeak frequency over the sample. The white dot in the middle of the image shows the place where the spectrum was colle...
The Raman spectra of the WS2/WSe2/p-Si heterostructures are shown in Fig. 3b. Typical Raman peaks for WSe2 and WS2 can be observed, and the positions of these peaks are consistent with previously reported values [37,38]. The enlarged Raman features of WSe2 are shown in Fig. S2a, ...
characteristic Raman peaks of WS2and SnS2can be distinctly observed. WS2shows the 2LA peak at 349.9 cm−1, E2gpeak at 355.8 cm−1, and A1gpeak at 420 cm−1. The A1gpeak of SnS2is observed at 313.4 cm−1. In order to reduce the contact resistances for better ...
In this work, we report a new straightforward Raman peak identification to discriminate monolayer WS2 crystals from layered and bulk samples. Our method is based on the A1g peak behavior. We show that through the comparison and analysis of other less convenient techniques that the strong splitting...
Raman spectra of the materials are shown in Supplementary Fig.12. The cross-sectional transmission electron microscopy (TEM) and EDS elemental mapping analysis distinguish W, S, and C components, thereby verifying the purity of the interface and the absence of interdiffusion at the van der Waals ...
The XRD pattern of exfoliated nanosheets shows a single strong peak at 14.3°. The other peaks were relatively weak. Raman spectroscopy Fig. 1b shows the Raman Spectra of exfoliated multilayer WS2 Conclusion Conclusively, we report facile synthesis of WS2 nanosheets. Through a controlled liquid ...
(JCPDS 04-003-5636). The XRD pattern of the processed WS2was consistent with the bulk one indicating that each of the two WS2was in the 2H phase. Raman modes located at 350 and 420 cm-1in Figure2(b)further confirmed that the processed WS2had all the characteristics of the 2H phase...
Interestingly, the Raman peaks corresponding to WC were observed at approximately 262, 329, 710.8, and 807.2 cm−1. These peak positions were quite overlapping as compared to those of WO3 [46]. Fig. 3 Raman spectra of the WS2 NFs and WS2–WC-–WO3 NH spheres Full size image The ...
Additionally, under resonant conditions, second-order Raman peaks is also observed. Resonant Raman spectra of our WS2 composite samples contain the second-order 2LA (M) peak at 351 cm−1 in addition to the first-order E12g(Γ), and the out-of-plane A modes at 355, and ~420 cm...
3c). The Raman bands of 2H-WS2 in this sample appear more distinct; in particular the combination mode of 2LA-E22g at ~320 cm−1 becomes visibly noticeable. Nonetheless, the peaks still lack the sharpness of CVD grown WS2 sheets and there is only a slight increase in the peak ...