Synthesis and structural analysis of C60–C70 two-component fullerene nanowhiskers

Publication date: 15 April 2015
Source:Journal of Crystal Growth, Volume 416
Author(s): Toshio Konno , Takatsugu Wakahara , Kun’ichi Miyazawa
C60–C70 two-component fullerene nanowhiskers (C60–C70NWs) were synthesized by liquid–liquid interfacial precipitation (LLIP) using various ratios of C70 to C60 and then analyzed using a focused ion beam processing apparatus (FIB-SEM), scanning electron microscopy (SEM), Raman spectroscopy, ultraviolet–visible (UV–vis) spectroscopy, X-ray diffraction (XRD) and high-performance liquid chromatography (HPLC). Both C60 and C70 were saturated in the supernatant solutions with fullerene compositions in the mother solutions ranging from 12.4 mass% C70 to 73.4 mass% C70. C60–C70NWs contained a small amount of rhombohedral phase, indicating polymerization of C60. The solid solubility limit of C70 in the C60 matrix was found to be 13.7 mass%. In addition to fine C60–C70NWs, thick C60–C70 needle-like crystals were formed. The thick C60–C70 needle-like crystals were fractured using a molybdenum probe in the FIB. The fractured surfaces of the C60–C70 needle-like crystals showed modulated structures with chemical compositions characteristic of spinodal decomposition. The activation energy of diffusion was determined to be 37.1kJ/mol.