The structural and morphological properties of fullerenols upon exposure to heat treatment have yet to be understood. Herein, the temperature-driven structural and morphological evolutions of fullerenols C60 (OH) and C70 (OH) were investigated. In situ spectroscopic techniques, such as variable-temperature X-ray diffraction and coupled thermogravimetric Fourier-transform infrared analysis, were used to elucidate the structural transformation mechanism of fullerenols. Both fullerenols underwent four-step structural transformation upon heating and cooling, including amorphous-to-crystalline transition, thermal expansion, structural compression, and new crystal formation. Compared to the initially nonporous amorphous fullerenol, the crystalline product exhibited microporosity with a surface area of 114 m2 g-1 and demonstrated CO2 sorption capability. These findings show the potential of fullerene derivatives as adsorbents.
Keywords: amorphous materials; crystallinity; fullerenol; microporous materials; structural transformation.
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