Introduction of Molybdenum Disulfide Molybdenum disulfide is an inorganic compound composed of molybdenum and sulfur. The main source of MoS2 is molybdenite. Molybdenum disulfide is a black solid powder with a metallic luster. It has a melting point of 1185 ° C, a density of 4.80 g/cm 3 (14 ° C), and a Mohs hardness of 1.0