Abstract
Carbon nanofibers were synthesized at 450–800 °C by the catalytic CVD method using alumina plate-supported nickel as catalyst and acetylene as carbon source. It was found that Ni/alumina catalyst exhibited a large catalytic effect on the growth of carbon nanofibers at the temperatures between 550 and 700 °C. TEM observation revealed that most of the carbon nanofibers synthesized at 550 °C had a coil-like shape, and many thick platelet nanofibers were found in the product at 700 °C. A growth model was proposed to explain the structural diversity of the carbon nanofibers. Although the carbon nanofibers showed low crystallinity, they can be easily graphitized at 2500 °C.