Explaining fullerene dispersion by using micellar solutions.

An effective computational strategy to describe the dispersion of C60 by surfactants is presented. The influence of parameters such as surfactant concentration and molecular length on the final morphology of the system is explored to explain the experimental results and to understand the incorporation of C60 inside micelles. Both neutral and charged amphiphilic molecules are simulated. The long-discussed problem of the location of fullerenes in micelles is addressed and C60 is found in the hydrocarbon-chain region of the micelles. If the available hydrophobic space increases, C60 is localized in the inner part of the micellar core. Short, charged amphiphilic stabilizers are more efficient at dispersing fullerenes monomolecularly. Two different phases of C60 are observed as the C60/surfactant ratio varies. In the first, aggregates of C60 are entrapped inside the micelles, whereas, in the second, colloidal nanoC60 is formed with surfactants adsorbed on the surface.