Preparation And Application Of Onion-like Carbon Nanoparticles

After the discovery of C₆₀ and other new carbon molecules, scientists discovered the carbon nanotubes and onion-like fullerene-a new nano-metric materials with integrated molecular structures. The potential application and special structures bring scientific improvement. Large-scale onion-like carbon nano-particles can be synthesized by heat treatment phenolic resin and carbon black by the aid of Fe, Co and Ni nitrate. The effects of catalyst species and size, temperature and carbon sources on the morphologies and structures of onion-like carbon nanoparticles were investigated by TEM, HRTEM, XRD, Ramon and HRSEM measurements.Usually, thermalsetting resins carbonized at～3000℃can produce similar fullerenes structure. Onion-like carbon nano-particles synthesized from phenolic resin have concentrically, quasi-spherically structures and high order. The diameters are about 30-50 nm. Under certain condition, some by-products such as bamboo-like carbon nanotubes, encapsulated carbon nanocapsules and short carbon nanotubes can be prepared. There are about 80% onion-like carbon nano-particles in the products. The carbon layers have preferential tropism and slit pores. With the decrease of catalysts (viz. the ratio of ferric nitrate to phenolic resin reducing from 1:4 to 1:32) , the diameter of onion-like carbon nano-paarticles turn large gradually. Macroscopically, the products are not a solid integer, but a shaggy appearance.In the experiment, carbon black was transformed into onion-like carbon nano-particles by catalytic heat treatment. The invert mechanism among the carbon structures were investigated through checking the catalytic action and the structural effects of Fe, Co and Ni on carbon black. When the small graphite layers convert into onion-like carbon nano-particles, Fe has better catalysis than Co and Ni and the products have higher purity and carbonization yield.The applications of lithium ion battery, electric storage hydrogen and lubricate oil additive develop notably. Simultaneously, we study the relations of different new carbon structures and transform it to carbon nanotubes. After the graphitization at 2800℃, their charge/discharge capacities improve greatly. Onion-like fullerenes as lubricate oil additive can enhance the friction property, loading, temperature and friction time. Because onion-like fullerenes operate as ball bearing, they replenish the rough surface and reduce the physically mechanical action.