Gas flow–directed growth of aligned carbon nanotubes from nonmetallic seeds

Kite growth is a process that utilizes laminar gas flow in chemical vapor deposition to grow long, well-aligned carbon nanotubes (CNTs) for electronic application. This uses metal nanoparticles (NPs) as catalytic seeds CNT growth. However, these NPs remain impurities the grown CNT. In this study, nanodiamonds (NDs) with negligible activity were utilized nonmetallic instead of catalysts because they are stable at high temperatures and facilitate low-defect CNTs without residual impurities. Results demonstrate successful over 100-$\mu$m-long by carefully controlling conditions. Importantly, we developed an analysis method secondary electron (SE) yield distinguish whether or not from The absence metallic tips was revealed SE mapping, whereas presence some kind same locations confirmed atomic force microscopy (AFM). These results suggest most aligned seeds, likely ND-derived NPs, via tip-growth mode. Structural characterizations crystallinity CNTs, relatively small diameters. study presents first use kite provides convincing alternative starting materials prepare findings pave way more convenient fabrication CNT-based devices, potentially simplifying production avoiding need removal