Towards Solutions of Single-Walled Carbon Nanotubes in Common Solvents (pages 1876–1881)
Shane D. Bergin, Valeria Nicolosi, Philip V. Streich, Silvia Giordani, Zhenyu Sun, Alan H. Windle, Peter Ryan, N. Peter P. Niraj, Zhi-Tao T. Wang, Leslie Carpenter, Werner J. Blau, John J. Boland, James P. Hamilton and Jonathan N. Coleman
Article first published online: 21 APR 2008 | DOI: 10.1002/adma.200702451
Spontaneous exfoliation of single-walled carbon nanotubes on dilution of dispersions in a common solvent, N-methyl-pyrrolidone, is demonstrated. The free-energy of mixing is negative, confirming athermal solubility. Scanning tunneling microscopy measurements show physisorption of the solvent to the nanotube (see figure). Experiments, supported by a simple model, show that successful solvents for nanotubes are those with surface tensions close to that of graphite.