title: Macroscopic wall number analysis of single-walled, double-walled, and few-walled carbon nanotubes by X-ray diffraction.
abstract: The layer number is of great importance for nanocarbon materials, such as carbon nanotubes (CNTs) and graphene. While simple optical methods exist to evaluate few-layer graphene, equivalent analysis for CNTs is limited to transmission electron microscopy. We present a simple macroscopic method based on the (002) X-ray diffraction peak to evaluate the average wall number of CNTs in the range from single- to few-walled. The key was the finding that the (002) peak could be decomposed into two basic components: the intertube structure (outer-wall contacts) and the intratube structure (concentric shells). Decomposition of the peaks revealed a linear relationship between the average wall number and the ratio of the intertube and intratube contributions to the (002) peak. Good agreement with CNTs having average wall numbers ranging from 1 to ∼5 demonstrated this as a macroscopic method for average wall number analysis.
authors: Nanotube Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8565, Japan. d-futaba@aist.go.jp
authors: Don N
authors: DN
authors: Futaba
authors: Takeo
authors: T
authors: Yamada
authors: Kazufumi
authors: K
authors: Kobashi
authors: Motoo
authors: M
authors: Yumura
authors: Kenji
authors: K
authors: Hata