Densification of Carbon Nanotubes During Growth

Abstract

Carbon nanotubes are highly attractive for research purposes due to their field emission properties. However, when the nanotubes are vertically aligned on a substrate to form a continuous film, screening effect is observed, which reduces the efficiency. To densify the tubes into bundles and eliminate this screening effect, costly lithography patterning of catalysts and post-growth chemical treatments have been previously reported. In this work, we report a novel, cheap, and reproducible technique of densifying the growth of carbon nanotubes by utilizing a colloidal catalyst and microwave plasma-enhanced chemical vapor deposition. A qualitative investigation was carried out, and a possible densification mechanism was proposed.