Synergistic Laser-Induced Crystallization of C ₆ ₀ Fullerene in Solutions

Fabrication of organic crystals with desired polymorphs and shapes is important in various scientific and industrial fields but is often challenging because of their weak driving force of crystallization. In this work, we demonstrated fabrication of C60 fullerene crystals with out-of-equilibrium polymorphs and shapes by synergistically leveraging laser trapping and photothermal effects, which can achieve formation of locally concentrated domains with ∼10% higher supersaturation than those achievable by optical forces or photothermal effects alone. This laser method enabled one to spatiotemporally control crystal nucleation in solutions, which has never been achieved by optical trapping-induced crystallization that requires focused irradiation to air/solution interfaces. We also succeeded in the fabrication of C60 fullerene crystals with metastable forms, high aspect ratio profiles, and large sizes, which ensures the advantages of this laser method for the fabrication of organic crystals with various properties.