Effects of impurities and lattice imperfections on the conductive properties of MoS2

The effects of vacancies on the electronic properties of transition metal dichalcogenide (TMD) semiconductors is studied and the absorption of water demonstrated by modeling molybdenum disulfide (MoS2) nanoscale devices. The simulations presented here combine molecular dynamics (MD), density functional theory (DFT), and non-equilibrium Green's function (NEGF) formalism. Combining these methods, the effects of single and double S vacancy and a single Mo vacancy on charge transport are detailed by looking at transmission functions and conduction paths. The contrast on the effect of double S vacancy and Mo vacancy is intriguing, with only hole transport and electron transport respectively, being affected by the defect. Adsorption of water and oxygen at defects, particularly grain boundaries, is demonstrated via MD simulations.