Chemical vapor deposition synthesis of carbon nanosprouts on calcined stainless steel

Bumped bamboo carbon nanotubes (carbon nanosprouts) were directly synthesized on calcined stainless steel by chemical vapor deposition. Using a mixture of CO and H-2 as the carbon precursor, dense carbon nanosprouts were formed on the surfaces of stainless-steel wire without external catalyst addition. The air calcination favours the formation of iron oxide nanoparticles with relatively small diameters, catalysing the synthesis of carbon nanosprouts with comparable trunk diameters. Transmission electron microscopy analysis shows that Fe2.5C is the active catalyst phase and catalyst deactivation is caused by graphitic layer encapsulation. The enhanced carbon precipitation of Fe catalyst, promoted by the carbon source dissociation or its synergism with other metal, is responsible for the generation of nanosprouts. (C) 2018 Elsevier B.V. All rights reserved.