Optimization of the liquid–liquid interfacial precipitation method for the synthesis of C₆₀ nanotubes

Tubular fullerene nanowhiskers called 'fullerene nanotubes' are composed of C₆₀ fullerene molecules (C₆₀ NTs) are synthesized at room temperature using the liquid–liquid interfacial precipitation method in the pyridine and isopropyl alcohol (IPA) system. The growth control of fullerene nanotubes is important for their chemical and physical properties as well as for their future applications. In the present study, we investigated the effect of light, water, solvent ratio and temperature on the synthesis of C₆₀ nanotubes. A marked development in the yield of C₆₀ NTs was achieved using dehydrated solvents, a solution with a volume ratio of 1:9 for pyridine: IPA, a growth temperature equal to 5℃C and by illuminating the C₆₀-pyridine solution with ultraviolet light (wavelength 302 nm) for 102 h. The synthesized fullerene nanotubes were characterized by different analytical techniques including Raman and Fourier transform infrared spectroscopy, optical microscopy, focussed ion beam scanning electron microscopy and transmission electron microscopy. (author)