Electric field tunable electronic structure in two dimensional van der Waals g-C2N/XSe2(X = 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/A. 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/A. At an electric field from 0.1 to 0.3 V/A, 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. (C) 2017 Elsevier Ltd. All rights reserved.