WSe2 (Tungsten Diselenide)
WSe2 is a semiconductor with an indirect band gap of ~1.3 eV, monolayer WSe2 has a direct band gap. The layers are stacked together via van der Waals interactions and can be exfoliated into thin 2D layers. Tungsten Diselenide belongs to the group-VI transition metal dichalcogenides (TMDC).
To buy WSe2 crystals please click here.
The WSe2 crystals produced at HQ Graphene have a typical lateral size of ~0.8-1 cm, are hexagonal shaped and have a metallic appearance.
We produce both n-type and p-type WSe2, having typical charge carrier densities of ~1015cm-3 at room temperature.
A selection of peer review publications on the WSe2 we sell can be found below.
| Crystal size | ~10 mm |
| Electrical properties | Semiconductor, p-type (we also have n-type available) |
| Crystal structure | hexagonal |
| Unit cell parameters | a = b = 0.328 nm, c = 1.298 nm, α = β = 90°, γ = 120° |
| Monolayer properties |  Link to C2DB containing calculated properties |
| Type | Synthetic |
| Purity | >99.995 % |
| Characterized by | XRD, Raman, EDX, Hall measurement |
| More information? | Please contact us by email or phone |
The single crystal WSe2 is characterized using:
XRD: single crystal and powder X-ray diffraction (D8 Venture Bruker and D8 Advance Bruker)EDX: Energy-dispersive X-ray spectroscopy for stoichiometric analysis
Raman: 785 nm Raman system
Hall measurement: Extraction of charge carrier density and doping in the Van der Pauw geometry.
Raman, XRD and EDX on WSe2:
Click on an image to zoom
HQ Graphene Wiki on:
WSe2 (Tungsten Diselenide)
1. H.C.P. Movva et al. "High-Mobility Holes in Dual-Gated WSe2 Field-Effect Transistors ", ACS
Nano, 2015, 9(10), 10402-10410, link to article:
http://pubs.acs.org/doi/abs/10.1021/acsnano.5b04611?journalCode=ancac3
2. B. Fallahazad et al. "Shubnikov-de Haas Oscillations of High-Mobility Holes in Monolayer and Bilayer WSe2: Landau Level Degeneracy, Effective Mass, and Negative Compressibility", Phys. Rev. Lett. 116, 086601 (2016), (also available on arxiv.org/pdf/1602.01073.pdf) link to article:
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.086601
3. R. Bertoni et al. "Generation and Evolution of Spin-, Valley-, and Layer-Polarized Excited Carriers in Inversion-Symmetric WSe2", Phys. Rev. Lett. 117, 277201 (2016), (also available on arxiv.org/abs/1606.03218) link to article:
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.117.277201