About Tungsten Disulfide WS2:
Tungsten disulfide is an inorganic compound composed of tungsten and sulfur. Tungsten disulfide chemical formula is 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 tungsten disulfide 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 (<~660 nm />~1.88 eV). In addition to the light of the appropriate wavelength, the reaction requires oxygen and water to proceed, where water is considered a catalyst for oxidation. The reaction products include tungsten oxide and sulfuric acid. Similarly, the oxidation of other semiconductor transition metal dihalides (S-TMD) (such as MoS2) has also been observed under ambient light and atmospheric conditions.
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 Tungsten disulfide price if you would like to buy tungsten disulfide 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%
W |
S |
Al |
As |
Cl |
Cu |
Fe |
Ni |
P |
Si |
O |
74.12 |
25.82 |
0.001 |
0.002 |
0.03 |
0.002 |
0.005 |
0.002 |
0.002 |
0.003 |
0.002 |
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 is used to make tungsten disulfide lubricant, tungsten disulfide grease.
Tungsten disulfide WS2 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.
Luoyang Tongrun Nano Technology Co. Ltd. (TRUNNANO) is a trusted global chemical material supplier & manufacturer with over 12-year-experience in providing super high-quality chemicals and Nanomaterials, including boride powder, nitride powder, graphite powder, sulfide powder, 3D printing powder, etc.
If you are looking for high-quality tungsten disulfide powder, please feel free to contact us and send an inquiry.
Q:What is tungsten disulfide used for?
A:WS 2 is used as a friction reducer for aerospace and aircraft components. In the injection moulding industry, it helps to reduce friction during the moulding process. Parts do not stick to the mould and release faster. It is also used in chains, vertical mills, bearings and gearboxes.
Q:Is tungsten disulfide toxic?
A: Human Health Data
Inhalation may cause nose and throat irritation. Most studies have shown insoluble molybdenum compounds to be toxicologically inert. Molybdenum dichloride may cause skin and eye irritation due to the abrasive nature of the powder.
Q:Is tungsten disulfide oxygen compatible?
A:The coating is unaffected by most solvents and is non-toxic and non-corrosive. It is insensitive to liquid oxygen and nitrogen and is unaffected by radiation.WS2 coatings may be attacked by free fluorine gas as well as hot sulphuric and fluorine acids.