Achieving ultrahigh concentrations of fluorescent single-walled carbon nanotubes using small-molecule viscosity modifiers.

Surfactant dispersion is a well-established method for stabilizing individual single-walled carbon nanotubes in aqueous solutions. However, achieving high concentrations of individually dispersed nanotubes with this technique has proven challenging. Here it is demonstrated that the introduction of viscosity-enhancing compounds such as sucrose can increase the maximum concentration of surfactant-dispersed single-walled carbon nanotubes by more than a factor of 100 while still retaining the optical properties of individual nanotubes. When these solutions are used as inks for methods such as inkjet printing, they retain their fluorescent properties even after the ink has dried.