▎ 摘　　要

The spin-polarized electronic transport properties of zigzag graphene nanoribbons (ZGNRs) and boron nitride nanoribbons (ZBNNRs) heterojunctions with a boron vacancy are investigated by using non-equilibrium Green's function and density functional theory, especially under an external electric field. The model we used in this paper is chosen from the last essay we researched, the I-V curves in the ferromagnetic states for (ZBNNR)(5)-(ZGNR)(3)-B-v devices are investigated, and the results show that with an external electric field, the heterojunctions are promising multifunctional devices in molecular spintronics due to their nearly perfect spin-filter effect, high rectification ratio and spin negative differential resistance properties at low biases. Mechanisms for such phenomena are proposed and these findings suggest a new opportunity for developing molecular spintronic devices.