▎ 摘　　要

Covalent functionalization of graphene is recently developed from the formation of sp(3) hybridized carbon atom (sp(3)-C) to the sp(3) hybridized nitrogen (sp(3)-N) at the anchoring site. Here, we investigated the electronic structures and transport properties of the zigzag graphene nanoribbons functionalized by covalently bonding of p-aminophenol (p-AP) molecule. First principles results demonstrate that the formed sp(3)-N plays a vital role in determining the electronic structure and transport properties of the system, resulting in a halfmetallic characteristic with a perfect spin-filtering behavior (100%). Interestingly, the performance of the spin-filtering is find to be insensitive to the sub-structures of the molecule. Our findings reveal the importance of sp(3)-N and suggest a new mechanism for realizing high-performance spin-filtering devices with functionalized graphene. (C) 2019 Elsevier B.V. All rights reserved.