Effects of the restructuring of Fe catalyst films on chemical vapor deposition of carbon nanotubes

We investigated the restructuring of Fe catalyst films during high temperature processing and its effects on the morphologies of carbon nanotubes (CNTs) arrays synthesized using the thermal chemical vapor deposition (CVD) techniques. Results show that annealing time and gas environment deeply influence the particle size distribution, which determines the morphologies of the corresponding CNT arrays. Fe particles with narrow size distribution were obtained after proper high temperature processing in NH3, from which higher purity CNT arrays with better-alignment and uniform diameter distribution have been grown.