First-principles study of B, C, N and F doped graphene-like MgO monolayer

•Formation energy of B, C, N and F doped MgO monolayer decreased in the order of B>C>N>F.•Band gaps of B, C and N doped MgO monolayer were tunable.•B, C and N doped MgO monolayers were magnetic upon doping.•F-doped MgO monolayer was predicted to be nonmagnetic metal.

Based on the first-principles calculations, we have investigated the stable geometries, electronic and magnetic properties of the graphene-like MgO monolayer with O atom substituted by B, C, N, and F atoms. The formation energy decreases in the order of B>C>N>F, which may be influenced by the different electronegativities. The band gaps of p-type doped MgO monolayers are tunable due to the emergence of impurity states within the band gap, while F-doped MgO monolayer realizes the transition from semiconductor to metal. The results show that p-type doped MgO monolayer exhibit magnetic behaviors due to polarizations of dopants and surrounding Mg or O atoms near the dopants, while no magnetism is observed in the case of F doped MgO monolayer. These results are potentially useful for spintronic applications and the development of magnetic nanostructures.