First principles study of single and multi-site transition metal dopant ions in MoS2 monolayer

Abstract

Using first-principles calculation, a systematic study on the effect of transition metal (TM: V, Cr, Mn, Fe, Co, Ni) dopant atoms in the MoS2 monolayer as potential spintronic, catalytic and optoelectronic materials were carried out. The electronic and magnetic properties of this monolayer changed due to the presence of the TM ion dopants. The calculated substitutional energies indicate that it is energetically favourable to introduce TM ions into the MoS2 lattice under the S-rich condition compared to the Mo-rich condition. The calculated binding energies also show that TM ions exhibit a dispersive distribution rather than the suggested multi-site configurations considered in the MoS2 lattice. This is because most of the considered dopant multi-site configurations of a particular dopant ion are not energetically favourable compared to the single site configuration. Generally, there is a reduction in the electronic band gap of doped MoS2 compounds as well extra absorption peaks in the absorption spectra. The calculated redox potentials of H2O splitting show that Cr doped MoS2 monolayer can be potential photo-reductants. This theoretical investigation provides further insight into the application of MoS2 as ultra-thin spintronic material in the case of V, Fe and Mn doped monolayers