▎ 摘　　要

We study the electron spin-charge transport properties through an aromatic molecule between two pyridines in conjunction with graphene electrodes by applying the nonequilibrium Green's functions in combination with the density functional theory. The computational result shows that, the multifunctions of perfect spin-filtering and spin-rectifying with efficiency approaching nearly 100%, giant magnetoresistance with ratio up to 105 and negative differential resistance effects, are exhibited in this all-carbon system. Importantly, these functionalities can be qualitatively adjusted by the oxygen absorption on molecule, the variation of the electrode initial magnetic orientations and the moleculepyridine connection, respectively. The physical and chemical mechanisms are revealed and discussed in terms of the spin-resolved transmission spectrum, the evolution of the frontier molecular orbitals, the local density of states around the Fermi level at zero bias, and the molecular projected self-consistent Hamiltonian. Our conclusion may indicate a direction for designing all-carbon spintronic nanodevices based on graphene. (C) 2017 Elsevier B.V. All rights reserved.