Hierarchical Self-Assembly of Water-Soluble Fullerene Derivatives into Supramolecular Hydrogels

Controlling the self-assembly of nanoparticle building blocks into macroscale soft matter structures is an open question and of fundamental importance to fields as diverse as nanomedicine and next-generation energy storage. Within the vast library of nanoparticles, the fullerenes—a family of quasi-spherical carbon allotropes—are not explored beyond the most common, C₆₀. Herein, a facile one-pot method is demonstrated for functionalizing fullerenes of different sizes (C₆₀, C₇₀, C_84, and C_90–92), yielding derivatives that self-assemble in aqueous solution into supramolecular hydrogels with distinct hierarchical structures. It is shown that the mechanical properties of these resultant structures vary drastically depending on the starting material. This work opens new avenues in the search for control of macroscale soft matter structures through tuning of nanoscale building blocks.