N-doped graphene with Curie temperature higher than room temperature is a good candidate for nanomagnetic applications. Here we report a kind of N-doped graphene that exhibits ferromagnetic property with high Curie temperature (>600 K). Four graphene samples were prepared through self-propagating high-temperature synthesis (SHS), and the doped nitrogen contents of in the samples were 0 at.%, 2.53 at.%, 9.21 at.% and 11.17 at.%. It has been found that the saturation magnetization and coercive field increase with the increasing of nitrogen contents in the samples. For the sample with the highest nitrogen content, the saturation magnetizations reach 0.282 emu/g at 10 K and 0.148 emu/g at 300 K; the coercive forces reach 544.2 Oe at 10 K and 168.8 Oe at 300 K. The drop of magnetic susceptibility at ~625 K for N-doped graphene is mainly caused by the decomposition of pyrrolic N and pydinic N. Our results suggest that SHS method is an effective and high-throughput method to produce N-doped graphene with high nitrogen concentration and that N-doped graphene produced by SHS method is promising to be a good candidate for nanomagnetic applications.

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With the synergistic effect of 3D RGO and Ni–Co–S nanosheets, a Ni–Co–S/RGO/NF electrode exhibits excellent electrochemical performance.

A self-propagating high-temperature synthesis (SHS) method to synthesize few-layer graphene (FLG) from magnesium and different carbon sources is demonstrated. These carbon sources include CaCO 3 , 3MgCO 3 •Mg(OH) 2 •3H 2 O, glucose, and polyvinyl alcohol (PVA). FLG produced by SHS method has a 3D porous structure with a special nanocrystallinity, and a low amount of defects. This fast, energy saving and low cost method is competitive as a candidate for industrial production of graphene for a wide range of applications. It is found that CaCO 3 are superior to others among these starting materials according to DSC properties. The dye-sensitized solar cell (DSC) with a FLG (produced from CaCO3) counter electrode (CE) achieves a power conversion efficiency higher than that obtained with a reference DSC using a Pt counter electrode. The charge transfer resistance of FLG DSC is 0.13 Ω cm 2 , which is more than thirty times lower than that of the DSC having a Pt counter electrode. SHS FLG has been demonstrated to be a promising alternative counter electrode in DSC.