Research on the Preparation and Spectral Characteristics of Graphene/TMDs Hetero-structures

Abstract

The Van der Waals (vdWs) hetero-structures consist of two-dimensional materials have received extensive attention, which is due to its attractive electrical and optoelectronic properties. In this paper, the high-quality large-size graphene film was first prepared by the chemical vapor deposition (CVD) method; then, graphene film was transferred to SiO2/Si substrate; next, the graphene/WS2 and graphene/MoS2 hetero-structures were prepared by the atmospheric pressure chemical vapor deposition method, which can be achieved by directly growing WS2 and MoS2 material on graphene/SiO2/Si substrate. Finally, the test characterization of graphene/TMDs hetero-structures was performed by AFM, SEM, EDX, Raman and PL spectroscopy to obtain and grasp the morphology and luminescence laws. The test results show that graphene/TMDs vdWs hetero-structures have the very excellent film quality and spectral characteristics. There is the built-in electric field at the interface of graphene/TMDs heterojunction, which can lead to the effective separation of photo-generated electron–hole pairs. Monolayer WS2 and MoS2 material have the strong broadband absorption capabilities, the photo-generated electrons from WS2 can transfer to the underlying p-type graphene when graphene/WS2 hetero-structures material is exposed to the light, and the remaining holes can induced the light gate effect, which is contrast to the ordinary semiconductor photoconductors. The research on spectral characteristics of graphene/TMDs hetero-structures can pave the way for the application of novel optoelectronic devices.

PVDF-HFP encapsulated WS2 nanosheets in droplet-based triboelectric nanogenerators for possible detection of human Na+/K+ ion concentration

“…Such occurrence of the shift can be attributed to the strong electronphonon coupling [33], arising from the interaction between H and C atoms of PVDF-HFP and S atoms WS 2 . Such an event has been witnessed in WS 2 when functionalized with Silicone or graphene [36,37].…”

Enhanced Performance of Transfer‐Free Graphene Transparent Conductive Films on Insulating Substrates by Introducing Array Nanostructure

“…It is difficult to see the specific morphology of graphene from Figure 3d, but the four‐probe test results prove that the substrate has conductivity, indicating the formation of graphene. Although graphene covers the surface of the AR layer, the wrinkles of graphene cannot be seen [25] . In order to further observe the morphology of graphene, the following characterizations were carried out.…”

“…Although graphene covers the surface of the AR layer, the wrinkles of graphene cannot be seen. [25] In order to further observe the morphology of graphene, the following characterizations were carried out.…”

2D van der Waals Heterojunction Nanophotonic Devices: From Fabrication to Performance

“…CVD is a precise method for controlling the growth of 2D materials and 2D heterostructures and vdWhs can also be fabricated using the CVD method. [59,60] Figure 3 shows a schematic of the WS 2 /MoS 2 vdWh fabricated by the CVD method, as well as the final morphology of this heterojunction. [45] In Figure 3c, the two triangles in the figure represent the direction of the MoS 2 and WS 2 layers, confirming the formation of the heterojunction.…”