Wafer-Scale Hyper-Porous Graphene Network With Intrinsic Ferromagnetism at Room-Temperature

We report a wafer-scale hyper-porous graphene network (HGN) with room-temperature intrinsic magnetism, which was revealed by both XMCD spectra at C K-edge and M-H curve, corresponding to a magnetic moment density of ∼0.06 μ_B/atom, 1000 times higher than in defected HOPG. The impurity effects on magnetism were excluded by XMCD and ICP-MS measurements. Atomic-resolution observations unveiled that the magnetism originate from dangling zigzag edges within HGN pores apart over 1.4 nm, which was proved by annealing treatment and DFT calculations. This work confirms that intrinsic carbon ferromagnetism with the same physical mechanism as in the microscale can be obtained in bulk carbon systems. It provides a novel platform to further explore the spintronic and magnetic applications of carbon allotropes.