EFFECTS OF CATALYSTS AND REACTION TEMPERATURE ON FORMATION OF VGCF IN VACUUM

Hollow carbon fibers were fabricated using the vacuum CVD method on a carbon fiber (CF) substrate by using Ni based catalyst and propylene as the source of carbon at 1?000?℃. The formation of such hollow fibers might be the consequence of growth by carbon atoms accumulating around the perimeter of a metallic cell. Meanwhile, a connected carbon fiber network was formed in the spaces in the CF substrate by using Fe based catalyst with the same CVD conditions. However, tree shaped nanometer scale fibers were fabricated with the same kind of Ni based catalyst, when the CVD temperature was increased to 1?100?℃. This is closely related to stable morphologies of the metallic liquid phase on the tip of the growing fiber with increased CVD temperature.