Insight into the Growth of Non-uniform Vanadium-Doped Molybdenum Disulfide for Tunable Electronic Properties

Element doping in two-dimensional (2D) materials can introduce novel physical–chemical properties, and the obtained crystals are widely used as platforms for investigating unique properties and as functional units for advanced applications. However, the uniformity of doping, as an important step to define the doping properties, is not yet fully understood. In this study, vanadium (V)-doped molybdenum disulfide (MoS₂) is used as an example to study the correlation between non-uniform doping and electronic properties. A thermodynamically stable doping structure was initially predicted theoretically and subsequently reached by a robust chemical vapor deposition method. The V atoms were dispersed non-uniformly throughout the MoS₂ lattice, leading to a doping concentration gradient in the V-doped MoS₂ conductive channel for corresponding field effect transistors. This work focused on the uniformity characteristics of element-doped 2D materials, an important but often ignored topic, and it will potentially help improve the reliability of 2D materials’ applications.