Two-dimensional materials with intrinsic
long-range ordered magnetic
moments have drawn a lot of attention. However, for practical applications,
whether or not the magnetism is stable in their nanostructures has
not been revealed. Here, based on the recently proposed magnetic penta-hexa-graphene,
we study the electronic and magnetic properties of its nanoribbons
(named PHGNRs). The results show that the PHGNRs have intrinsic robust
magnetic moments that are different from zigzag graphene nanoribbons,
where the magnetic moments caused by the edge effect are vulnerable.
Moreover, the magnetic ground states, namely, ferromagnetic (FM) or
antiferromagnetic (AFM), can be transformed by changing the width
of PHGNRs. Most interestingly, under the FM ground state, the spin-polarized
electronic properties reveal that the zigzag PHGNRs transform from
spin-gapless semiconductors (SGSs) to half-metals, as the width of
nanoribbons increases, while all the armchair PHGNRs are magnetic
semiconductors. Furthermore, by considering different edge effects
caused by the residual carbon atoms on the edges, the PHGNRs can further
derive different types of SGSs, as well as half-metals. Our work suggests
that the PHGNRs possessing intrinsic robust magnetic moments have
potential applications in the field of spintronic devices.