▎ 摘　　要

Using the non-equilibrium Green's function method and the spin-polarized density functional theory, we investigate the magnetism and spin resolved transport properties of hetero-structures based on zigzag graphene nanoribbons (ZGNRs) with edge hydrogenation (H) and oxidation (O). It is found that a perfect spin filtering effect can be realized on O-ZGNR-H/H-ZGNR-H in both parallel and anti-parallel spin configurations. Interestingly, an excellent dual spin filtering behavior can be obtained on O-ZGNR-H/H2-ZGNR-H, which is independent of the width of the nanoribbon. Our results indicate that the hetero-structure holds promise for spintronic devices in future. (c) 2015 Elsevier B.V. All rights reserved.