Carbon nanotubes stack alignment

Wang, C., Ryu, K., De Arco, L.G., Badmaev, A., Zhang, J., Lin, X., et al., 2010a. Synthesis and device applications of high-density aligned carbon nanotubes using low-pressure chemical vapor deposition and stacked multiple transfer. Nano Res. 3, 831-842. 

The structure of CNTs consists of one, two or more, graphene sheets rolled up to make the tubes leading to variations from single (S), double (D) and multi-wall (MW) carbon nanotubes, respectively. Nanotubes naturally align themselves into ropes held together by van der Waals forces, more specifically, pi-stacking. The nature of the dispersion problem for CNTs is rather different from other... 

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