Investigation and Optimization of Temperature Dependent Parameters for Growing Millimeter-Long Vertically Aligned Carbon Nanotubes

Abstract

This study aimed to investigate effects of temperature dependent parameters on vertically aligned carbon nanotube (VACNT) forest height such as catalyst treatment temperature and growth temperature and optimize these parameters to grow long VACNT forests. These growth parameters were examined and optimized on samples including three different thicknesses of Fe catalyst layers which catalyze VACNT growth. Heights of VACNT forests grown on different Fe catalyst layers linearly decreased at various rates with the increment of the catalyst treatment temperature from 500 ℃ to 800 ℃. Moreover, optimum growth temperature to grow long VACNTs was found to be independent from Fe catalyst layer thickness while their height distributions showed variations. As a result of optimization of these parameters, we have found that it is possible to grow millimeter long VACNT forests from all three Fe catalyst layers with substantially low gas flows in 30 min growth. Raman spectroscopy approved that disorder of grown VACNTs is very low. Use of low gas feedstock, achieved in this study, ensures green and economic production of VACNTs.