Glassy Porphyrin/C60Composites: Morphological Engineering of C60Fullerene with Liquefied Porphyrins

Morphological control of C60fullerene using liquefied porphyrins (1and 2) as the host matrices was explored. Slow evaporation of the solvent of the equimolar mixture of porphyrin and C60in toluene afforded the porphyrin/C60composite with a 3:1 molar ratio. The stoichiometric binding behaviors suggest that specific porphyrin–C60interactions operate the formation of the porphyrin/C60composites, as corroborated by spectroscopic and thermal properties, and glazing-incidence wide-angle X-ray diffraction. Under the bulk conditions, the conventional thermodynamic advantage of multiple binding cooperativity for molecular recognition is unlikely to explain the stoichiometric binding behaviors. Instead, we propose a size-matching effect on the porphyrin–C60interaction in the bulk porphyrin matrices, i.e., “supramolecular solvation”. The glassy nature of the porphyrin matrices was transmitted to C60through the specific interaction, and the porphyrin/C60composites adopted glassy states at room temperature.