Electric field tunable electronic structure in two dimensional van der Waals g-C2N/XSe2(XÂ =Â Mo, W) heterostructures

The electric field effects on the electronic structure of g-C2N/XSe2 (X = Mo, W) heterostructures are investigated by first-principles calculations. The g-C2N/MoSe2 heterostructure is an indirect semiconductor at an electric field from −0.1 to 0.3 V/Å. The band gap is 0.66, 0.54, 0.45, 0.39 and 0.34 eV, which almost changes linearly with the electric field. The maximum spin splitting at K point is 188 meV. The g-C2N/WSe2 heterostructure is still an indirect semiconductor at an electric field of −0.1 and 0 V/Å. At an electric field from 0.1 to 0.3 V/Å, the heterostructure with the valence band at Fermi level is a p-type semiconductor, where the band gap is 0.32, 0.26, 0.19, 0.12 and 0.06 eV and the maximum spin splitting at K point is 444 meV. Moreover, near Fermi level, the conduction band mainly comes from monolayer g-C2N, but the valence band comes from XSe2. Our results can bring much significant information on the potential applications in spintronic and field effect devices.

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