Tungsten Disulfide (WS2) Pristine Flakes in Solution, 100 ml

Tungsten Disulfide (WS₂) Pristine Flakes in Solution, 100 ML

WS₂ Pristine Flakes are nanoscale crystals dispersed in ethanol/water solution. If separated from solution, nano-WS₂ forms bright-green crystals, that look different from silver-grey crystals of bulk WS2.

Properties:

Lateral Size: 50-150 nm

Thickness: 1-4 monolayers

Purity in dry phase: >99%

Solution Concentration: 26 mg/L

Solution is stable under ambient conditions

This solution can be easily deposited onto a substrate or surface of your choice to form a thin film coating.

SEM image of thin-film WS₂ after the solution was used to coat SiO₂

UV-Visible Absorption Spectrum

Bulk WS₂ forms dark gray hexagonal crystals with a layered structure. They are not chemically active and can only be dissolved by a mixture of nitric and hydrofluoric acids. Each W(IV) center of WS₂ is occupying a trigonal prismatic coordination sphere, which is bound to six sulfide ligands. The sulfur centre is connected to three tungsten centres, which are pyramidal. The trigonal prisms are layered, sandwiching tungsten atoms between layers of sulfur atoms.¹

Depiction of WS₂ Crystal Structure¹

WS₂ in its monolayer form has recently been under particular recognition for its intriguing electrical and optical properties. Bulk WS₂ is generally an n-type semiconductor with an indirect bandgap (~1.4 eV). On the other hand, monolayer WS₂ has a direct bandgap of ~1.9 eV, and can be useful in low-power switching devices.

WS₂ Raman Spectrum

Preparation Method: Solution-Based Exfoliation

Applications:

Transistors

Flexible Displays

Optics

WS₂ Research

Inks

Thin Semiconducting Films

We can do custom formulations, and fill orders for large volumes of the solution! Contact us for more details.

Check out our WS₂, MoS₂, BN trial pack if you would like to test all three NEW products by clicking HERE!

These materials have been used in publications, including:

Layered memristive and memcapacitive switches for printable electronics, Bessonov et al. Nature Materials.

Academic references:

Electronics and optoelectronics of two-dimensional transition metal dicalcogenides, Wang et al. Nature Nanotechnology, 7 (2012), pp. 699-712

Extraordinary room-temperature photoluminescence in WS₂ monolayers, Gutierrez et al. arXiv:1208.1325 [cond-mat.mes-hall]

Quantitative Determination of the Band Gap of WS₂ with Ambipolar Ionic Liquid-Gated Transistors, Braga et al. Nano Letters, 12 (2012). pp. 5218-5223

¹Adapted from the Wikimedia Commons file Molybdenite-3D-balls.png