C60 buckyball molecules were partially truncated by a controlled oxidation at 400 °C and 2 bar oxygen pressure to create unique pore textures suitable for hydrogen adsorption. Pore textural analysis and density measurement confirmed the success of cage-opening and the creation of pore structures accessible to gas molecules. The specific surface area of the C 60 sample were increased from below detection to a measurable value (BET: 85 m2/g). Raman spectral study showed that the three main bands of C60, Hg(1), Ag(1) and Ag(2) remained and significant defects were created after the C60 fullerenes were partially oxidized. XRD and SEM measurements suggested that the C60 fullerenes lost their crystallinity and the crystal surfaces were etched after the oxidation step. Hydrogen adsorption on the C60 fullerenes were measured at three temperatures (77, 143 and 228 K) and hydrogen pressures up to 150 bar. Hydrogen adsorption capacity on C60 fullerenes at 77 K at 120 bar was more than tripled (from 3.9 to 13 wt.%) after the C60 fullerenes were partially oxidized. The average heat of adsorption of hydrogen on the partially oxidized C60 fullerene molecules (2.38 kJ/mol) is within the range of the reported values of heat of adsorption on other porous adsorbents.
ASJC Scopus subject areas
- Materials Science(all)