Effects of Iron Catalyst Size on the Growth Behavior of Vertical Aligned Carbon Nanotube Arrays

This research examines the growth mechanisms of Vertically Aligned Carbon Nanotube arrays (VACNTs). The synthesis of VACNTs involved the utilization of an iron catalyst deposited onto a substrate surface. Silicon substrates were coated with alumina and iron by magnetron sputtering technique. Through the application of SEM, EDX, AFM, TEM, and ellipsometry techniques, a thorough parametric investigation was conducted to elucidate the operational principles of the catalyst and its practical feasibility. Results underscore a direct relationship between the catalyst's thickness and the characteristics of the resulting VACNTs. Shown that the thickness of thin iron catalyst films of 2-3 nm allowed obtaining VACNTs with the best ID/IG bonds ratio according to Raman spectra.