title: Sensitive G-band Raman features for the electrical conductivity of multi-walled carbon nanotubes.
abstract: We have studied the structural parameters of catalytically grown highly disordered multi-walled carbon nanotubes that were heat treated at temperatures between 1200 degrees C and 2600 degrees C in an argon atmosphere. Rather than the interlayer spacing or the R value (the intensity of the D band divided by the intensity of the G band), we found that the half width at half maximum intensity of the G band was the most sensitive parameter that is correlated with the altered electrical conductivity of an individual carbon nanotube that had been heat treated at high temperatures. This is because one-dimensional nanocarbons exhibit a preference for two-dimensional structural development along the length of the tube due to the limited mobility of carbon atoms along the circumferential direction. Tubes heat treated at 2200 degrees C exhibited both a high electrical conductivity and an absence of lithium-ion intercalation, and thus are the best conductive filler for the active materials of lithium-ion batteries for long-term stability.
authors.affiliation: Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan.
authors.forename: Yoong Ahm
authors.initials: YA
authors.lastname: Kim
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kakegawa
authors.forename: Kazunori
authors.initials: K
authors.lastname: Fujisawa
authors.forename: Daisuke
authors.initials: D
authors.lastname: Shimamoto
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Muramatsu
authors.forename: Jin Hee
authors.initials: JH
authors.lastname: Kim
authors.forename: Yong Chae
authors.initials: YC
authors.lastname: Jung
authors.forename: Takuya
authors.initials: T
authors.lastname: Hayashi
authors.forename: Morinobu
authors.initials: M
authors.lastname: Endo
authors.forename: Mauricio
authors.initials: M
authors.lastname: Terrones
authors.forename: Mildred S
authors.initials: MS
authors.lastname: Dresselhaus