WSe2 Solution

This product contains WSe₂ flakes solution in ethanol. The WSe₂ solution has been developed by ultrasonic treatment of bulk WSe₂ high quality crystals synthesized through vapor transport (CVT) technique. Since the starting material (CVT grown WSe₂ crystals) is highly crystalline, ultrasonic treatment to delaminate WSe₂ layers yields highly crystalline WSe₂ mono-, few-, and some thick layers suspended in ethanol solution. The crystallinity of WSe₂ nanomaterials has been confirmed through electron energy dispersive spectroscopy (EDAX), Raman spectroscopy (FWHM<5 cm^-1), and scanning electron microscopy (SEM) measurements. Depending on the thickness of the layers, flakes deposited on different substrates produce light emission (photoluminescence). Lateral sizes of WSe₂ flakes deposited onto different substrates range from ~10nm - ~10 mm while thickness range from 1L to 10s of layers.

Note on volume, concentration, and solvent type: To reduce shipping costs, we ship supersaturated 2D solutions (~80-120 mg/L depending on the type of 2D layers). However, supersaturated solutions can be diluted to produce ~250-500mL of solution to deposit 2D layers onto desired substrates through simple and cost-effective spin-casting process. In our product, ethanol is used (and recommended) as the dispersant solvent owing to its environmental stability, thermal stability, dispersant properties, and non-contaminating nature. However, if your research needs other solvents, please contact us at support_at_2dsemiconductors.com 

Sample Properties

Specifications

• Identification. WSe₂ solutions created by delamination of WSe₂ crystals (grown by CVT method) through ultrasonication technique
• Physical dimensions. 1 to 10 layers in thickness (thicker pieces might be observed depending on usage) and 10nm to 10 microns in lateral dimensions.
• Smoothness. Atomically smooth surface with roughness < 0.35 nm.
• Purity. 99.999% purity as determined by nano-SIMS measurements
• Stability. High environmental and dispersant stability.
• Crystallinity. Highly crystalline nanomaterials. No amorphous sheets, contaminants, or hidden secondary phases.
• Dispersant solution. Ethanol is highly recommended though other solvents can be prepared on demand.
• Support. 2Dsemiconductors USA is an American owned, regulated, and operated company. Our customers are well-protected by international as well as strict American customer laws and regulations. We give full technical support and guarantee your satisfaction with our well-established customer

Supporting datasets

Scanning electron microscope images taken from WSe₂ solution deposited onto SiO₂/Si substrates [Left] Dense limit and [Right] Dilute limit

EDS elemental composition data collected from WSe₂ solutions

Raman spectroscopy data collected from variety of 2D solutions

Frequently asked questions

Q1: Are these solutions good for catalytic measurements?

A: Yes, our 2D solutions are commonly used by catalysis community

Q2: What is the volume of the solution? 

A: Each order can either contain 2mL of supersaturated monolayer solution (~200mg/L) or dense 20mL solutions (~20mg/L). We recommend using 2mL solutions as this will cut down the shipping charges and shipping times.

Q3: Are these 2D solutions consist of 100% monolayers? 

A: This will depend on your requirements. We can design monolayer, few-layer, multi-layer, and even bulk layered solutions. Please identify what kind of solution (material type) you prefer to use during check out.

Q4: How about the solution types?

A: This will also depend on your application. We have capability to accommodate IPA, H2O, DMF, NMP, and many others. Just let us know what you have in mind.