Tuning of electronic states and magnetic polarization in monolayered MoS₂ by codoping with transition metals and nonmetals

Doping is an effective way to modulate the properties of two-dimensional (2D) materials to cater to new applications. In this work, the codoping effects of transition metals (TM) and nonmetals (NM) on the electronic states and magnetic polarization in monolayered MoS₂ are investigated by first-principles calculation. The NM-doped MoS₂ possesses semiconducting characteristics, but the B-, N-, and F-doped ones are magnetic showing a magnetic moment of 1.0 μ _B per dopant. The metal dopants can induce magnetization in the monolayered MoS₂, and the magnetic moment is related to the total number of outer electrons in the TM. In the case of codoping, the S and Mo atoms are substituted by the NM and TM atoms, respectively, and hence, the semiconducting characteristics are maintained despite the reduced band gap. Spin polarization resulting from codoping depends on the number of outer electrons in the TM and NM dopants. Spin polarization occurs if the total number of the outer electrons is odd, but does not if it is even. The magnetic moment of the codoped monolayered MoS₂ is always 1 μ _B and magnetism is enhanced considerably by (V + B) and (Mn + F) codoping.