A fabrication method of organic nanocrystals using stabilizer-free emulsion

We report a novel method of producing monodispersed polycyclic aromatic hydrocarbon nanocrystals as a result of crystal growth in a stabilizer-free oil-in-water emulsion. The emulsion was prepared by dispersing a hot organic solvent including target molecules into an aqueous medium at the same temperature as the solvent, and nucleation and crystal growth were then induced in the emulsion by decreasing the temperature. The emulsifier of the organic solvents was easily removed from the dispersion medium, and we were able to obtain pi-conjugated organic nanocrystals such as tetracene, C-60 fullerene, and anthracene at high dispersion concentrations.