Abstract
We examine the possibility of controlling nanotube growth and simultaneously manipulating the nanotube properties by adding during the growth process, elements in minute amounts (such as nitrogen, phosphorous, and sulfur) that are different from carbon and the metal catalyst. This procedure is shown to be capable of producing bamboo-type morphologies, heterodoped carbon nanotubes, and Y-junctions. This also represents a critical step towards tailoring properties and controlling nanotube architectures, thus promoting the development of novel materials with unusual electronic applications. The underlying formation mechanisms that lead to the observed structures and morphologies are elucidated using wide-ranging electronic structure calculations that reveal the fundamentally different nature of nitrogen, phosphorous and sulfur during carbon nanotube growth.
