Paracrystalline Structure of Glass-Like Carbons

This study reports on structural characterization of a series of glass-like carbons obtained by pyrolysis of polyfurfuryl alcohol at 600, 800, 980, and 2700 degrees C. The atomic scale structure of the prepared materials has been studied using wide-angle X-ray scattering technique. The acquired diffraction data were analyzed in reciprocal space as the structure factor and in real space in the form of the pair distribution function to reveal the structural attributes such as number of hexagonal network layers, size of the layers, interlayer correlations, interlayer and interatomic distances. The parameters have different effects on the diffraction intensity and the pair distribution function and are verified in reciprocal and real diffraction space simultaneously. The obtained results show that the structure of the glass-like carbons consists of defective graphite-like domains which size increase with the pyrolysis temperature. The heat treatment leads to a noticeable ordering of coherently scattering domains of glass-like carbon in directions perpendicular to graphene-like layers. However, paracrystalline type of disorder within individual layers manifesting itself in decrease in intensity and broadening of the diffraction lines is preserved in the atomic structure even at heat-treatment temperature of 2700 degrees C.