The electronic and bonding properties of nitrogenated carbon nanotubes (N-CNTs) exposed to chlorine plasma were investigated using C and N K-edge x-ray absorption near-edge structure (XANES) and scanning photoelectron microscopy (SPEM). The C and N K-edge XANES spectra of chlorine-treated N-CNTs consistently reveal the formation of pyridinelike N-CNTs by the observation of 1s ->pi(*)(e(2u)) antibonding and 1s ->pi(*)(b(2g)) bonding states. The valence-band photoemission spectra obtained from SPEM images indicate that chlorination of the nanotubes enhances the C-N bonding. First-principles calculations of the partial densities of states in conjunction with C K-edge XANES data identify the presence of C-Cl bonding in chlorine treated N-CNTs. (C) 2007 American Institute of Physics.
Ray, SC., Pao, CW., Tsai, HM., Chiou, JW., Pong, WF., Chen, CW., Tsai, MH., Papakonstantinou, P., Chen, LC., Chen, KH., & Graham, WG. (2007). Electronic structures and bonding properties of chlorine-treated nitrogenated carbon nanotubes: X-ray absorption and scanning photoelectron microscopy studies. Applied Physics Letters, 90(19), 192107. https://doi.org/10.1063/1.2737392