Stability, bonding and electronic structures of halogenated MoS2 monolayer: A first-principles study

Highlights: • Halogen monomers adsorbed on MoS₂ stably inducing magnetic moment of 1μB. • Long range antiferromagneticallyantiferromagnetically couplings are found between halogen adatoms. • Only semifluorinated MoS₂ is stable among the four semihalogenated configurations. • Semifluorination leads to a transition from semiconductor to metal of MoS₂ monolayer. Surface decoration is a convenient and effective way to tune the properties of two dimensional (2D) materials. Here we performed a first-principles study of the functionalization of MoS₂ monolayer by halogen atoms (F, Cl, Br and I). The adsorption of halogen monomer, halogen dimer on MoS₂ monolayer, and the halogenation of one side of MoS₂ were studied. Halogen monomers can adsorb stably on MoS₂ inducing impurity states and magnetic moment of 1.0 μ_B per supercell. Long range antiferromagnetic (AFM) couplings are found between halogen adatoms. Semihalogenated Cl- and Br-MoS₂ can be in nonbonding or bonding state, with the nonbonding state being more energetic favorable. Semihalogenated I-MoS₂ can only be in nonbonding state. Semifluorinated F-MoS₂ can stabilize in bonding state with a titled configuration and large binding energy. MoS₂ monolayer is transferred from a semiconductor to metal upon semifluorination.