Molybdenum disulfide

Structure of molybdenum disulfide

Molybdenum disulfide has sandwich-like structure The layer of molybdenum atoms lies between two layers of sulfur atoms. The two layers of S atoms are 6.26A apart the room each whereas the distance between S atom layer and Mo atom layer is 3.13A. The shear strength in a direction parallel to the layers is due to poor interlaminar attraction.

MoS₂ forms a film having low frictional resistance, by filling up the flaws: this makes the surface evener. Further, the particle slide over each other as the surfaces of machinery is in motion.

Properties of molybdenum disulfide

• It has a very low coefficient of friction.
• It is stable in air up to 400⁰C.
• In absence of air, it can be used up to a temperature of 600⁰C.
• It does not show good lubrication in moist air.
• It is softer than graphite and has higher specific gravity than graphite.

Uses of MoS2

• It can be used as a dry powder or with solvents and greases.
• It can be used for temperature and high-velocity situations.