Supramolecular soft and hard materials based on self-assembly algorithms of alkyl-conjugated fullerenes

Abstract

Dimensionally controlled and hierarchically assembled supramolecular architectures in nano/micro/bulk length scales are formed by self-organization of alkyl-conjugated fullerenes. The simple molecular design of covalently attaching hydrophobic long alkyl chains to fullerene (C₆₀) is different from the conventional (hydrophobic–hydrophilic) amphiphilic molecular designs. The two different units of the alkyl-conjugated C₆₀ are incompatible but both are soluble in organic solvents. The van der Waals intermolecular forces among long hydrocarbon chains and the π–π interaction between C₆₀ moieties govern the self-organization of the alkyl-conjugated C₆₀ derivatives. A delicate balance between the π–π and van der Waals forces in the assemblies leads to a wide variety of supramolecular architectures and paves the way for developing supramolecular soft materials possessing various morphologies and functions. For instance, superhydrophobic films, electron-transporting thermotropic liquid crystals and room-temperature liquids have been demonstrated. Furthermore, the unique morphologies of the assemblies can be utilised as a template for the fabrication of nanostructured metallic surfaces in a highly reproducible and sustainable way. The resulting metallic surfaces can serve as excellent active substrates for surface-enhanced Raman scattering (SERS) owing to their plasmon enhancing characteristics. The use of self-assembling supramolecular objects as a structural template to fabricate innovative well-defined metal nanomaterials links soft matter chemistry to hard matter sciences.