| As a class of novel porous materials,ordered mesoporous carbon (OMC)possesses more remarkable properties,such as a narrow pore distribution,high specific surface area,chemical inertness,and good hydrothermal and mechanical stability.It has been attracting considerable attention because of potential applications in gas separation,catalyst supports,and energy storage/conversion.Typically,the mesoporous materials containing Fe,Co,Ni nanoparticles have fascinating magnetic properties and the carbon coating could protect the magnetic nanoparticles against environmental degradation.The property of the magnetic materials makes them find suitable application in magnetic separation.In this thesis,the influence of synthetic conditions on the formation of ordered mesoporous carbon/Ni composite was investigated.The OMC/Ni nanocomposites with well-dispersed nickel metal were prepared, and their magnetic performances were investigated.Magnetic Ni/OMC composites with a cubic structure of Im3m symmetry were obtained in a basic medium of nonaqueous solution by a solvent-evaporation-induced self-assembly(EISA)approach using F127 as the structure directing agent,resorcinol-formaldehyde(RF)polymer as the main carbon source and[Ni(H2O)6](NO3)2 as metal source.The effects of the nickel loading content and the carbonization temperature on the morphologies,pore features,structures and magnetic properties of these Ni/OMC composites were investigated using the thermogravimetric analysis,X-ray diffraction, nitrogen sorption,transmission electron microscopy and vibrating-sample magnetometer measurements.It is worth mentioning that the hydrogen bonding plays a key role in driving the self-assembly of[Ni(H2O)6](NO3)2,F127 and RF to form periodically ordered composites.The nickel nanoparticles were well-dispersively embedded into the ordered mesoporous carbon walls. The Ni particle sizes,estimated using the Scherrer equation from the wide-angle XRD diffraction line,become bigger from 19 nm to 25 nm as the metal loading and the carbonization temperature increase.The resulting composite with the Ni content of 12 wt%obtained at 700℃has a BET surface area of 309m2/g,a pore volume of 0.19cm3/g,and a narrow pore size distribution centered at 3.52 nm.With the increases of the content of Ni and carbonization temperature from 400 to 1000℃, both the saturation magnetization and the remanent magnetization of Ni/OMC samples increase.In addition,the excellent acid-resistant property of the magnetic materials makes them find suitable application in magnetic separation.
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