Room temperature magnetism in reduced graphene oxide (rGO)

Graphene-oxide (GO) and reduced graphene-oxide (rGO) are known to offer many potentials for a wide range of applications. A new method of development based on the concepts of Hummer’s and modified Hummer’s methods is used to synthesize GO, which was subsequently chemically reduced to magnetic rGO using sodium borohydride (NaBH4). The morphological quality, elemental analysis, functional groups, and crystalline size of graphite, GO, and rGO have been studied. GO and rGO exhibit wrinkled-stacked flakes and crumpled thin sheets, respectively, in contrast to graphite, which has a platelet-like surface. Fourier transform infrared spectroscopy analysis demonstrates that GO has more oxygen-rich functional groups than rGO and graphite. The distinctive peaks for graphite, GO, and rGO are revealed by x-ray diffraction at 26.4°, 10.6°, and 17.4°, respectively. Furthermore, using a vibrating sample magnetometer, rGO shows ferromagnetic behavior with a magnetization of 0.32 emu/g and a coercivity of 205 Oe at 300 K, while graphite and GO do not. The presence of passivated C–H bonds converted rGO from a non-magnetic carbon material into a defect-driven, exchange-coupled magnetic system. The outcomes open a new route for new magnetic materials and their potential for future applications in spintronics and quantum computing at room temperature.