Effect of catalyst on morphology of carbon nano-materials prepared in a nano-agglomerate bed

Carbon nanotubes (CNTs) were prepared in batch-process by catalytic chemical vapor deposition (CCVD) using a nano-agglomerate bed, Effects of transition metal catalysts on morphology and output of CNTs were studied. The experimental results showed that better quality of CNTs can be achieved at low carbon yield with Fe-catalysts, with Ni-catalysts, the carbon yield is much higher but the quality of CNTs produced is worse; with Co-catalyst, a novel carbon nano-material with needle shape which has not yet been reported is discovered. Effects of catalyst supports on preparation of CNTs in the nano-agglomerate bed is also very important. CNTs with better micro-structure and higher purity can be achieved using Fe-catalysts with few supports, but their activity is not enough high and the carbon yield is low. CNTs can not be produced using pure Ni nanoparticle catalyst Without any support. According to these experimental results, it is clear that suitable catalyst components, even dispersion of active centers and proper pyrolysis rate are key factors for preparation of CNTs in batch-process in the nano-agglomerate bed.