First-principles study of the origin of magnetism induced by intrinsic defects in monolayer MoS₂

Highlights: • Mo absorption and Mo substituted at S site induce the magnetism. • The origin of the magnetism is mainly from the Mo adatom and substitutional atom. • S_Mo and V_Mo realize the n-type and p-type semiconductor behavior, respectively. - Abstract: The structural, electronic and magnetic properties of intrinsic defects in monolayer MoS₂ have investigated systematically by first-principles calculations based on density functional theory. The results show that S vacancy and S adsorption is the most favorable intrinsic defect under Mo-rich and S-rich conditions, respectively. Mo atom adsorbed on monolayer MoS₂ and Mo atom substituted at S site induced the spin-polarization, which gives rise to total magnetic moment of 4.0μ_B and 2.0μ_B, respectively. The magnetism is mainly origin from the Mo adatom and the Mo substitutional atom, respectively. For the Mo and S adsorption, the Mo atom and S atom prefer to adsorb on top of the Mo atom and the S atom, respectively. In addition, S_Mo and V_Mo can realize the n-type and p-type semiconductor behavior, respectively. These predictions are useful for the spintronic devices designs.