Thermal stability and high-temperature degradation of pristine bisazafullerene (C59N)2 were analyzed by infrared and Raman spectroscopy in the temperature range from 300 to 745 K. The spectra showed a reversible temperature dependence up to 550 K. For higher temperatures an irreversible degradation into disordered graphite was found. Approximately 55% of the material resisted a thermal treatment of 745 K for several hours. A mechanism involving a low stationary concentration of C59N° monomer radical species and a slow graphitization is proposed for the thermolysis of the material. The remarkable thermal stability of pristine bisazafullerene (C59N)2 is ascribed to the low stability of the C59N° monomer radical species, the high activation energy for graphitization, and the absence of other reaction partners under high vacuum conditions.
ASJC Scopus subject areas