title: "Cloning" of single-walled carbon nanotubes via open-end growth mechanism.
abstract: Using the concept of "cloning", we report herein a rational approach to grow single-walled carbon nanotubes (SWNTs) with controlled chirality via an open-end growth mechanism. Specifically, by using open-end SWNTs as "seeds/catalysts" (without metal catalysts), "new/duplicate" SWNTs could be grown and cloned from the parent segments via an open-end growth mechanism. Using this strategy, we have measured more than 600 short seed segments and have found that the yield of cloning is relatively low (around 9%). This yield can be greatly improved up to 40% by growing SWNTs on quartz substrate. Atomic force microscopy and micro resonance Raman spectroscopy characterization indicate that the parent nanotube and the duplicate nanotube have the same structure. These findings provide a potential approach for growing SWNTs with controlled chirality, which are important for the application of SWNTs in nanoelectronics.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Laboratory for the Physics and Chemistry of Nanodevices, College of Chemistry and Molecular Engineering, Peking University, Beijing, People's Republic of China.
authors.forename: Yagang
authors.initials: Y
authors.lastname: Yao
authors.forename: Chaoqun
authors.initials: C
authors.lastname: Feng
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.forename: Zhongfan
authors.initials: Z
authors.lastname: Liu