Enhanced Conductivity for Carbon Nanotube based Materials through Supramolecular Hierarchical Self-Assembly

Abstract

The currently limited comprehension of hierarchical control over out-of-equilibrium (dynamic) self-assembly processes in nanoscience and nanotechnology has limited the exploitation of multicomponent systems in the design of new nanostructured functional materials. In our contribution, molecular building blocks with tailored nanoscale anisotropic supramolecular self-assembly behavior enable the creation of mesoscale percolation networks of multiwall carbon nanotubes through collinear interconnections at the microscale. This strategy affords polymeric composites with tunable properties at the macroscale, where the organization mechanism is regulated by dynamic self-assembly at 4 hierarchical levels of auto- organization. Such multilevel self-assembly system reduces up to 8- fold the nanotube concentration required for percolation and enhances conductivity up to 6 orders of magnitude against blanks, thus yielding anisotropically semiconducting and conducting materials. Our approach is based on casting-from-solution, thus simplifying preparative steps when compared to state-of-the-art electron carrier counterparts such as single-walled carbon nanotube-, graphene- or indium-tin-oxide-based technologies. Finally, promising material transparency levels can be reached across the visible and near- infrared regimes for compositions above the percolation threshold, which provides new opportunities beyond the current spectral restrictions in commercial transparent conductors.