The characteristics of n- and p-type dopants in SnS2 monolayer nanosheets.

Based on density functional theory, the characteristics of n- and p-type impurities are investigated firstly by means of group V and VII atoms substituting sulfur atoms in the SnS2 monolayer nanosheets. Numerical results show that the formation energy and transition levels depend highly on the atomic size and electronegativity of the impurity atom. The formation energies increase with the increasing impurity atom size for each considered doping case. For group V atom-doped SnS2 monolayer nanosheet systems, the calculations of the transition level indicate that N, P or As doping is not effective for p-type conductivity. However, for group VII atom doping cases, F, Cl, Br and I impurities can offer effective n-type carriers in the SnS2 monolayer nanosheets.