Molybdenum disulfide (MoS₂) is a chemical compound made up of molybdenum and sulfur. It is a transition metal dichalcogenide, known for its layered structure, where each layer consists of a single plane of molybdenum atoms sandwiched between two planes of sulfur atoms. This unique structure gives MoS₂ interesting properties, such as high lubricity and electrical conductivity. MoS₂ is widely used in various applications, including as a lubricant in machinery and as a semiconductor in electronic devices. Its ability to function as a catalyst also makes it valuable in chemical reactions, particularly in the production of hydrogen from water, contributing to advancements in energy technology.