From isotope labeled CH₃CN to N₂inside single-walled carbon nanotubes

Abstract

The observation of one-dimensional N₂ inside single-walled carbon nanotubes raises the questions, how are the N₂ molecules formed and how do they manage to make their way to this peculiar place? We have used N(15) and C(13) isotope labeled acetonitrile during the synthesis of single-walled carbon nanotubes to investigate this process. The isotope shifts of phonons and vibrons are observed by Raman spectroscopy and X-ray absorption. We identify the catalytic decomposition of acetonitrile as the initial step in the reaction pathway to single-walled carbon nanotubes containing encapsulated N₂.

Controlling pyridinic, pyrrolic, graphitic, and molecular nitrogen in multi-wall carbon nanotubes using precursors with different N/C ratios in aerosol assisted chemical vapor deposition

“…Recently, Kamberger et al detected N 2 molecules in single-walled CNTs, produced from an isotope labeled acetonitrile, and explained their existence by the reaction of two CRN radicals at or inside the catalyst particle. 48 According to NEXAFS and XPS data, this reaction is less likely to occur in N-MWCNTs, but cannot be excluded. In summary, we illustrate the formation mechanism of N-MWCNTs and the distribution of different forms of nitrogen along the nanotube layers as depicted in Fig.…”

Field emission properties of aligned CNx nanotube arrays synthesized by pyrolysis of a ferrocene/acetonitrile aerosol at different temperatures

“…). A low‐energy component at 398.5 eV corresponds to pyridinic nitrogen, next component located at 401.0 eV is attributed to graphitic nitrogen, and high‐energy component around 405.0 eV is due to N 2 molecules, which are trapped in the nanotube core or located between the nanotube layers . A component at 403.1 eV is often related to pyridine‐N‐oxide , while as predicted by quantum‐chemical calculations the clustered graphitic nitrogen atoms might have the similar binding energy .…”