Carbon nanofilaments (CNFs) with platelet structure have been prepared by liquid phase carbonization using porous anodic alumina template, and their lithium ion insertion/extraction properties have been examined as a function of heat treatment temperature and filament diameter. The CNFs heat-treated at 1000°C reveal higher capacitance and higher rate capability compared with those heat-treated at higher temperatures. Further, it is found that higher reversible capacity is obtained for the CNFs with reduced diameter. The reversible capacity of highly graphitized CNFs formed at 2800°C is less than 200 mA h g -1 at a current density of 50 mA g -1 , being far lower than the theoretical capacity (372 mA h g -1 ) of graphite.A probable reason is the presence of loop at the edge of graphene layers.

Platelet structure carbon nanofilaments of ~30 nm in diameter have been prepared by heating a mixture of porous anodic alumina template and poly(vinyl)chloride powders in an argon atmosphere, and the change in their structure and morphology with heat treatment temperature, ranging from 600 to 2800°C, has been examined using XRD, scanning electron microscopy, transmission electron microscopy and nitrogen gas adsorption measurements.The diameter of the carbon nanofilaments formed does not change with heat treatment temperature, being in agreement with the pore diameter of the template, while their length is reduced with the temperature. The platelet-type orientation of graphene layers is evident even at 600 o C with the layer structure further developing with increasing heat treatment temperature. The carbon nanofilaments formed at lower temperatures have micropores, while those formed at higher temperatures do not have porosity. Highly graphitized carbon nanofilaments have been obtained after heat treatment at 2800°C, with another characteristic structural feature being presence of loops at the edge of graphene layers formed at 2800°C.

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