Tungsten Disulfide WS2 Powder CAS 12138-09-9

About Tungsten Disulfide WS2:
Tungsten disulfide is an inorganic compound composed of tungsten and sulfur, with the chemical formula WS2. This compound is part of a group of materials called transition metal dihalides. It naturally appears as a rare tungsten ore. This material is part of certain catalysts used for hydrodesulfurization and hydrodenitrogenation.
WS2 uses a layered structure similar to MoS2 or the same type of MoS2, instead of a coordination sphere with W atoms (instead of molybdenum atoms) in a triangular prism. Due to this layered structure, WS2 formed inorganic nanotubes, which were discovered after heating a thin sample of WS2 in 1992.
Most of the WS2 forms dark gray hexagonal crystals with a layered structure. Like the closely related MoS2, it has the characteristics of a dry lubricant.
Although people have long believed that WS2 is relatively stable in ambient air, recent reports on single-layer WS2 oxidation in the environment have found that this is not the case. WS2 is converted to tungsten oxide in a single layer form by a photooxidation reaction fairly quickly (within a few days in ambient light and atmosphere). The oxidation process includes visible wavelength light easily absorbed by the single-layer WS2 (
WS2 is also attacked by a mixture of nitric acid and hydrofluoric acid. When heated in an oxygen-containing atmosphere, WS2 is converted to tungsten trioxide. When heated in the absence of oxygen, WS2 will not melt but will decompose into tungsten and sulfur, but the decomposition temperature is only 1250°C.
Historically, the separation of monolayer WS2 used a chemical exfoliation method, that is, inserting lithium from n-butyl lithium (in hexane), and then stripping the inserted Li compound by ultrasonic treatment in water. WS2 is also shed by treatment with various reagents such as chlorosulfonic acid and lithium halide. Feel free to send an inquiry to get the latest price if you would like to buy tungsten disulfide WS2 powder in bulk.

Tungsten Disulfide details:
Tungsten Disulfide particle size: FSSS=0.4 to 0.7 μm, FSSS=0.85 to 1.15μm.  80nm
Tungsten Disulfide purity: 99.9%

How is Tungsten Disulfide WS2 produced?
1. Roasting decomposition method:
Tungstic acid reacts with ammonia water under stirring at 57-60°C for 3 hours, and the heat preservation naturally settles for more than 16 hours. The generated ammonium tungstate reacts with hydrogen sulfide gas to generate ammonium tetrathiotungstate after high-temperature roasting and decomposition into tungsten disulfide.
H2WO4+2NH3·H2O→(NH4)2WO4+2H2O
(NH4)2WO4+4H2S→(NH4)2WS4+4H2O
2(NH4)2WS4+3O2→2WS2+4NH3+2S+2SO2+H2O
2. Tungsten reacts very slowly with liquid sulfur. WS2 can be formed by passing sulfur vapor to red hot tungsten. Tungsten is mixed with stoichiometric sulfur bloom and reacted in a nitrogen atmosphere at 800°C for 24 hours to form WS2, such as reacting at 6MPa and 1800°C to form orthorhombic WS2.
3. Using ammonium tetrathiotungstate as the raw material, heating and decomposing the ammonium tetrathiotungstate under the condition of isolating the air, the temperature rises from room temperature to 700-1200℃ with a temperature gradient of 100-200℃/hour during heating. After being kept at this temperature for 24 to 48 hours, it is then reduced to room temperature with a temperature gradient of 30 to 110°C/hour, and the material is discharged and crushed.
The preparation method of ultrafine scaly crystal tungsten disulfide used for lubricants has simple process equipment, does not pollute the environment, and is safe and reliable in operation, and can produce tungsten disulfide with stable quality, high purity, and ultrafine crystal structure of hexagonal crystal system.

Applications of Tungsten Disulfide WS2:
Tungsten disulfide (WS2) or tungsten disulfide is a very smooth dry film friction coating. The friction coefficient of WS2 is extremely low, 0.03, which is lower than PTFE, graphite or molybdenum disulfide (MoS2). Compared with many other WS2, it has unparalleled performance in terms of lubricity, non-stick, low friction, wears life and rated size. It has a wide range of applications in transistors, sensors, photocatalysis, electronic equipment, etc. Tungsten disulfide powder has good solubility in water and ethanol.
WS2 is an excellent release material for plastic molds, extrusion molds and other demolding applications.
WS2 can eliminate the need for hydraulic oil, or can be used with petrochemical oil, grease, synthetic oil, silicone valve and hydraulic oil. It has an affinity for the fluid layer and maintains the fluid layer. It helps to keep oil or grease on the surface, thereby further improving the lubrication effect.
When the thickness is less than 1 micron, small parts can be coated without tolerance problems.
WS2 is also a fairly inert and non-toxic material that has been used in medical equipment and food processing applications.
WS2 replaces customer base materials through high-speed processes at ambient temperature. It does not make the substrate continuous or warped.
WS2 can be used alone or combined with our PVD hard coating to improve durability.

Storage Condition of Tungsten Disulfide WS2 Powder:
Damp reunion will affect WS2 powder dispersion performance and using effects, therefore, Tungsten Disulfide WS2 Powder should be sealed in vacuum packing and stored in cool and dry room, the Tungsten Disulfide WS2 Powder can not be exposure to air. In addition, the WS2 powder should be avoided under stress.

Packing & Shipping of Tungsten Disulfide WS2 Powder:
We have many different kinds of packing which depends on the Tungsten Disulfide WS2 Powder quantity.
Tungsten Disulfide WS2 Powder packing:vacuum packing, 100g, 500g or 1kg/bag, 25kg/barrel, or as your request.
Tungsten Disulfide WS2 Powder shipping:could be shipped out by sea , by air, by express?as soon as possible once payment receipt.