Formation Of Conical Carbon Structures On Vapor-Grown Carbon Filaments

We report two novel conical carbon structures of nano-to-micrometer dimensions that spontaneously grow on the surface of carbon filaments produced by thermal decomposition of certain hydrocarbons. The first carbon structure occurs in the form of an inverted truncated cone attached with its base to the surface of a carbon filament. Another carbon structure grows in the form of a conical spike with an apex angle of 6 °. Interestingly, these two structurally dissimilar carbon species can grow adjacent to each other