Transition Metal Dichalcogenides (TMDs)

Transition metal dichalcogenides (TMDs) are a class of compounds composed of a transition metal (such as molybdenum or tungsten) and a chalcogen element (like sulfur, selenium, or tellurium). These compounds typically have the chemical formula MX₂, where M represents the transition metal and X is the chalcogen. TMDs are known for their layered structures, similar to graphite, with strong in-plane bonding and weak out-of-plane interactions, allowing layers to be easily separated.

2D TMDs properties include the ability to change electronic characteristics from indirect to direct bandgap when thinned down to a single layer, which is critical for applications in photonics and valleytronics. They exhibit a range of electronic properties from metallic to semiconducting, making them highly interesting for various applications in electronics and optoelectronics. They are particularly noted for their potential in the development of novel devices such as transistors, sensors, and solar cells.