First-principles study of a molecular adsorption of fluorine on monolayer MoS2

Abstract

We have performed density functional theory (DFT) based first-principles calculations to study the stability, geometrical structures and electronic properties of pure monolayer Molybdenum disulphide (MoS₂) and Fluorine (F₂) adsorbed monolayer MoS₂ within the DFT-D2 level of approximations. Present study shows that a F₂ molecule adsorbed MoS₂ monolayer system is stable. From the geometry and in- formation of adsorption energy of F₂ molecule on the different occupation sites of  MoS₂ monolayer, it has been found that Fluorine prefers atomic adsorption above sulphur (S) atom. The binding energy per equivalent molecular Fluorine above the sulfur (S) atom is found to be 1.83 eV. The electronic structure calculations of MoS₂ and F₂ adsorbed MoS₂ monolayer shows that there is a band gap of 1.14 eV and 1.01 eV respectively, at the Fermi level. Further, the symmetry of total DOS for up and down spin calculations reveals that the F₂ adsorbed MoS₂ monolayer is non-magnetic as similar to that of pure MoS₂ monolayer. The projected density of states (PDOS) of a F₂ adsorbed MoS₂ monolayer is studied to understand the weighted contributions of different orbitals.

BIBECHANA 13 (2016) 50-59