Electronic and magnetic properties of Co doped MoS2 monolayer

Abstract

First principle calculations are employed to calculate the electronic and magnetic properties of Co doped MoS2 by considering a variety of defects including all the possible defect complexes. The results indicate that pristine MoS2 is nonmagnetic. The materials with the existence of S vacancy or Mo vacancy alone are non-magnetic either. Further calculation demonstrates that Co substitution at Mo site leads to spin polarized state. Two substitutional CoMo defects tend to cluster and result in the non-magnetic behaviour. However, the existence of Mo vacancies leads to uniform distribution of Co dopants and it is energy favourable with ferromagnetic coupling, resulting in an intrinsic diluted magnetic semiconductor.

Prospects of spintronics based on 2D materials

“…Theoretical models are typically built for situations far more ideal than experimental environment and thus could be unrealistic, particularly in view of small supercells typically used in most first‐principles calculations. Many studies found that the calculated property depends on the size of the supercell . The calculated magnetic properties are also quite sensitive to structural details.…”

“…In contrast, TMs like Fe, Co, and Ni show a FM exchange with the S, Se, and Te atoms, which results in a very weak FM coupling for TM dopants with large separations. For Co‐doped MoS 2 , Wang et al also found from their first‐principles calculations that two substitutional Co Mo defects tend to cluster and result in nonmagnetic behavior. This tendency of clustering and nonmagnetic behavior can be prevented by the existence of Mo vacancies which leads to uniform distribution of Co dopants and FM coupling.…”

“…Direct adsorption of metal atoms on the surfaces of TMDs and other 2D materials would in general face the same problem as graphene. Due to inertness of the surfaces, metal dopants may cluster together . However, compared to graphene, there are more possible adsorption sites on 2D materials such as TMDs and phosphorene (see Figure ).…”

“…Similar to graphene, vacancies and other point defects in 2D materials can anchor metals on their surfaces and reduce the diffusivity and formation of metal clusters . Magnetic properties of TM‐doped MoS 2 have been investigated in many first‐principles studies which consistently predicted that Mn‐, Fe‐, and Co‐doped MoS 2 are magnetic . A comprehensive first‐principles study of TM‐doped MoS 2 was carried out by Cheng et al In addition to the above TM atoms, they found that Zn‐, Cd‐, and Hg‐doped monolayer MoS 2 are magnetic, while for the other dopants in the VIIB to IIB groups magnetism is suppressed by Jahn‐Teller distortions.…”

Room‐Temperature Ferromagnetism in MoTe2 by Post‐Growth Incorporation of Vanadium Impurities

“…Such potential applications of magnetic vdW materials have recently sparked considerable interest in investigating magnetism of bulk ferromagnetic materials thinned to a single layer [1][2][3][4] or the emergence of ferromagnetism of paramagnetic bulk materials at the monolayer limit. [7][8][9][10][11][12] Recent experimental results suggest that 1T-2H phase boundaries in MoSe 2 , [13][14][15] edges in WS 2 or MoS 2 , [16][17][18][19] adsorbate induced defect states, [20] or substitutional doping of transition metals in 2D materials [21][22][23] can result in defect-or dopant-induced ferromagnetic ordering in these systems. [7][8][9][10][11][12] Recent experimental results suggest that 1T-2H phase boundaries in MoSe 2 , [13][14][15] edges in WS 2 or MoS 2 , [16][17][18][19] adsorbate induced defect states, [20] or substitutional doping of transition metals in 2D materials [21][22][23] can result in defect-or dopant-induced ferromagnetic ordering in these systems.…”