Nitrogen-doped carbon nanotubes synthesized with carbon nanotubes as catalyst

Abstract

Nitrogen-doped carbon (CN x) nanotubes were synthesized with carbon nanotubes (CNTs) as catalyst by detonation-assisted chemical vapor deposition. CN x nanotubes exhibited compartmentalized bamboo-like structure. Electron energy loss spectroscopy and elemental mapping studies indicated that the synthesized tubes contained high concentration of nitrogen (ca. 17.3 at.%), inhomogeneously distributed with an enrichment of nitrogen within the compartments. X-ray photoelectron spectroscopy analysis revealed the presence of pyridine-like N and graphitic N incorporated into the graphitic network. The catalytic activity of CNTs for CN x nanotube growth was ascribed to the nanocurvature and opening edges of CNT tips, which adsorbed C n/CN species and assembled them into CN x nanotubes.