Influence of boundary types on rectifying behaviors in hexagonal boron-nitride/graphene nanoribbon heterojunctions

We investigate the effect of boundary types on the rectifying behaviors in heterojunction composed of zigzag graphene and hexagonal boron-nitride (BNC) hybridized nanoribbons by employing nonequilibrium Green's functions in combination with the density-functional theory. The results demonstrate that the rectifying behavior is strongly dependent on the boundary types, while little affected by the width of BNC hybridized nanoribbons. It is noteworthy that the maximum rectifying ratio of the system at finite bias can be high up to orders of 107 in which atoms carbon in graphene nanoribbon are totally connected with atoms nitrogen in boron-nitride nanoribbon. The mechanism is proposed for these phenomena. (C) 2015 Elsevier B.V. All rights reserved.