Effective n-type F-doped MoSe2 monolayers

Using a first-principles method, based on the Vienna Ab-initio Simulation Package (VASP), we have studied the electronic structure, formation energy and transition level of a MoSe2 monolayer doped with V and VII atoms. The numerical results show that the dopant atoms can induce magnetism, except for in the case of the As-doped system. Specifically, N- and F-doped systems exhibit magnetic nanomaterial properties, P and As-doped systems display metallic features, and in the cases of Cl-, Br- and I-doped systems, the systems exhibit half-metallic ferromagnetism (HMF). The formation energy calculations indicate that this can be more effective for achieving n-type and p-type doped MoSe2 under Mo-rich experimental conditions. However, for the systems doped with group V atoms, the transition level decreases with increasing atomic radius, but that of those doped with VII atoms increases with increasing atomic radius. By comparing the results, we find that the transition level is only 31 meV in F-doped MoSe2 monolayers, which indicates that F impurities can offer effective n-type carriers in MoSe2 monolayers.