Origins of Height Distribution within Carbon Nanotube Arrays

Abstract

We investigated the phenomenon of non-uniform height distribution within CVD-grown carbon nanotube (CNT) arrays. This phenomenon is related to the activity of the catalyst which is affected by the deposition of the carbon source and the subsequent formation of pyrolysis products on the catalyst. We developed a model that considers the effects of deposition of the carbon source as well as the fact that the pyrolysis products also accumulate at the edges of CNT arrays. This model also illustrates that carbon source deposition results in moderate growth over large areas, whereas the pyrolysis products hinder growth significantly over small areas. Together, the two have a competitive effect on CNT growth and bring about the height distribution feature.