Can molybdenum disulfide be developed as a lubricant additive indefinitely?

Molybdenum disulfide is a compound composed of two elements: molybdenum and sulfur, with the chemical formula MoS2. This compound is a transition metal dihalide, which has a silver-black luster and exists in the form of molybdenite. Molybdenite is the most common molybdenum-containing ore. Molybdenum disulfide crystals usually exist in the form of powder, which is insoluble in dilute acid and not easily oxidized. From the outside, molybdenum disulfide is very similar to graphite and is often used as a solid lubricant due to its low coefficient of friction and high durability.

Molybdenum disulfide (MoS2) is one of the most common natural minerals and is often used as a solid lubricant in people's daily life. MoS 2 has a blue-gray or black appearance, has good chemical stability, heat and humidity resistance, and its surface is smooth with metallic luster and smoothness. The essence of MoS 2 is a transition metal sulfide, which is composed of three atomic layers. Between the two layers of sulfur atoms is a layer of molybdenum atoms, so it has morphological specificity. The covalent bonds between atoms are strong, but the connections between layers are weak. Therefore, when external pressure is applied during friction, the layers are easier to roll, and the molecular layer is easily broken to form a sliding surface. When deformation and rolling occur, the level of external pressure can be greatly enhanced; secondly, it is beneficial to reduce the relative friction area, and thereby reduce the friction coefficient, thereby minimizing the reduction of damage, which in turn increases The life span of the components. In short, MoS 2 is a lubricating additive with wireless development potential.

Preparation method of molybdenum disulfide

In the application of MoS 2, the study of its preparation method is the main problem. Only by preparing MoS2 with good morphology and excellent properties can it be used well and create unlimited development opportunities for the application of nanoparticles. At present, there are many methods for preparing MoS 2, usually including hydration heating method, chemical vapor deposition method, surfactant promotion method and physical mechanical method.

 Chemical vapor deposition

The chemical vapor deposition method has simple process, high product purity, low production cost, and can prepare molybdenum disulfide with high quality, large size and excellent performance. It is a relatively common method. Preparation of MoS2 nanomaterials. He Dawei and so on. Large-scale single crystal molybdenum disulfide was prepared on a sapphire substrate by a simplified chemical vapor deposition method under normal pressure. Molybdenum disulfide is a regular triangular monolayer with a side length of about 50 μm.

Although this method has many practical applications, HS may be present in the actual preparation process, so it is necessary to treat the exhaust gas accordingly. In addition, in this link, the appearance of the product lies in the flow and pressure of the gas phase. Under the volatility of dry batches, the forms presented are different, so the law also needs to continue to study and expand new fields and methods.

Physical Mechanical Method

For physical and mechanical methods, its control is simple and the product output is very effective. Deng Baihan et al. 100um linear graphene and 10um MoS 2 were prepared by micromechanical force method, and the number of graphene layers was identified by Raman spectroscopy. Carried out data processing, fitting and theoretical analysis. The spherical structure of MoS 2 combined with the base lubricant will perform very well in terms of its lubricating effect. In the actual output link, the repeatability is very poor and cannot be consistent with the appeal of large-scale output.

Heat of Hydration

In the actual application process, the highest and most extensive preparation method for nano MoS2 is the hydration heating method, and the materials developed for nano MoS2 have small specifications and excellent wear resistance.

Sun Jiaojiao and other materials, using ammonium molybdate tetrahydrate and L-cysteine as raw materials, are operated at 200°C for 24 hours through a hydrothermal method to prepare low-cost, high-performance non-platinum hydrogen evolution electricity catalyst. The preparation process of MoS 2 is completed.

The hydrothermal method has a short reaction period, simple operation, environmental protection, and high product purity, which has won unanimous praise and love from inquirers. It has become a key part of nano-molybdenum disulfide research and development.

Surfactant promotion method

For the surfactant-assisted method, the reaction process is stable and accompanied by dispersion, which can well control the appearance of the product and has great development potential. Therefore, the structure of nanomaterials around MoS 2 can be controlled and designed by selecting various types of surfactants.

Bai Geling et al. used the above method to prepare nano-MoS 2 by using PEG-20000 as a coating agent during the operation, and used Span-80 as a dispersant to surround 1% MoS 2 nanospheres and ultrafine disulfides. The preparation of molybdenum micropowder compound lubricating oil was carried out, and its rolling friction performance was systematically studied.

Overview of molybdenum disulfide

The unique sandwich structure of molybdenum disulfide (MoS2) gives it excellent lubrication, catalysis and other properties, and has great potential in the fields of friction, lubrication and catalysis. Based on the lubrication mechanism of molybdenum disulfide, research on its surface modification is reviewed, including surface organic coating, precipitation reaction coating, intercalation modification, etc.; at the same time, the current application fields of molybdenum disulfide are summarized, such as Self-lubricating thin layer, intercalated battery, high lubricity coating, etc. Catalysts, etc., and look forward to its future research directions.

Application of molybdenum disulfide

Molybdenum disulfide is mainly used in lubricating oil and grease to improve its wear resistance, abrasion resistance and extreme pressure performance. Due to its excellent physical and chemical properties, such as adjustable band gap, large specific surface area, abundant edge parts, good chemical properties and other stability, nano-molybdenum disulfide is used in optoelectronic devices, catalysis, lithium ion batteries and supercapacitors, and lubrication fields. , The huge application value is one of the hotspots of continuous research.

Molybdenum disulfide is an important solid lubricant, especially suitable for high temperature and high pressure. It is also diamagnetic, can be used as a linear photoconductor and a semiconductor with P-type or N-type conductivity, and has rectification and energy functions. Molybdenum disulfide can also be used as a catalyst for the dehydrogenation of complex hydrocarbons. It is also known as the king of advanced solid lubricants. Molybdenum disulfide is a solid powder made by changing the molecular structure of natural molybdenum concentrate after chemical purification. The color of the product is black, silver gray, metallic luster, smooth to the touch, and insoluble in water. The product has the following advantages: good dispersibility and non-blocking. It can be added to various greases to form a non-sticky colloidal state,

The main function of molybdenum disulfide used in friction materials is to reduce low-temperature friction, increase high-temperature friction and reduce ignition loss. It is volatile in friction materials.

Anti-friction: The particle size of the supersonic jet crushed molybdenum disulfide is 325-2500 mesh, the particle hardness is 1-1.5, and the friction coefficient is 0.05-0.1, so it can reduce friction when used in friction materials;

Increase friction: Molybdenum disulfide is not conductive, and there are copolymers of molybdenum disulfide, molybdenum trisulfide and molybdenum trioxide. When the temperature of the friction material rises sharply due to friction, the molybdenum trioxide particles in the copolymer expand with the temperature, thereby playing a role. Increase the effect of friction;

Anti-oxidation: Molybdenum disulfide is prepared through chemical purification and comprehensive reaction, and its PH value is 7-8, which is weakly alkaline. It covers the surface of the friction material to protect other materials and prevent them from being oxidized, especially to prevent other materials from falling off and increase adhesion;

The price of molybdenum disulfide

The price of MoS2 friction modifier molybdenum disulfide varies randomly with the production cost, transportation cost, international situation and the market supply and demand of MoS2 friction modifier molybdenum disulfide. Provide a full set of customized services, providing high-quality, low-cost nanomaterials and chemicals. If you are looking for MoS2 friction modifier molybdenum disulfide, please feel free to send an inquiry to get the latest price of MoS2 friction modifier molybdenum disulfide.

Suppliers of molybdenum disulfide

Tanki New Materials Co.,Ltd is a supplier of MoS2 friction modifier molybdenum disulfide, with extensive experience in the performance, application and cost-effective manufacturing of advanced and engineered materials. The company has successfully developed a series of powder materials (the best engine oil additive for nano-gold steel and stone, lithium stearate, nano-copper and nano-oil additives), high-purity targets, functional ceramics and structural devices, and provide OEM services.