Comparison of structure and yield of multiwall carbon nanotubes produced by the CVD technique and a water assisted method

Multiwall carbon nanotubes (MWNTs) were synthesized using chemical vapor deposition (CVD) technique and a water assisted method. Both methods produced MWNTs, which were characterized by SEM, TEM and Raman studies. It was observed that as far as quality is concerned, MWNTs produced by water assisted method are superior as the method does not employ any metal catalyst. However, as far as yield is concerned, CVD is a better method. Multiwall carbon nanotubes produced by water assisted method suffer from the drawback of low yield but have an advantage of production of multiwall carbon nanotubes without using any metal catalyst, at ambient pressure, in an environment friendly manner and using a simple and cost-effective apparatus. (C) 2010 Elsevier B.V. All rights reserved