Simultaneous alignment and dispersion of carbon nanotubes with lyotropic liquid crystals

We demonstrate that single-wall carbon nanotubes (SWCNTs) can be macroscopically aligned by means of templating in a lyotropic nematic liquid crystal (LC), a self-assembling anisotropic fluid with orientational but no translational order. The CNTs spontaneously adopt the alignment of the host, as we verify by means of resonant Raman spectroscopy. The aqueous LC host, based on the surfactant SDS, simultaneously keeps the nanotubes well dispersed over time scales of months or longer. The LC can be loaded with CNTs to almost the same extent as the standard isotropic 1% surfactant solutions normally used for dispersing CNTs without any optically visible bundling occurring.