▎ 摘　　要

Graphene, which possesses unique nanostructure and excellent properties, is considered a low cost alternative to carbon nanotubes in nanocomposites. In this paper, we demonstrate a facile in situ reduction approach for the synthesis of reduced graphene oxide/Ni (RGO/Ni) nanocomposites with different morphologies. The concentration of nickel ions has a great influence on the morphology of the RGO/Ni nanocomposites and an interesting RGO-wrapped nanostructure was obtained. Magnetic studies reveal a room-temperature ferromagnetic behavior of the RGO/Ni nanocomposites. The catalytic activities of the RGO/Ni nanocomposites were investigated for the reduction of p-nitrophenol by NaBH4. It was found that the nanocomposites show higher catalytic activity compared with the unsupported Ni nanoparticles. The catalytic performance of the RGO/Ni nanocomposites was even better than the RANEY (R) Ni catalyst. Moreover, after completion of the reaction the nanocomposite catalyst can be easily re-collected from the reaction system by a magnet. Thus, the RGO/Ni nanocomposites obtained in this work may find applications in catalysis, data storage, targeted drug transportation and magnetic resonance imaging technologies.