Structure and electrochemical activity of fullerite C{sub}60 films

摘要

In this paper the results of structure investigation of the C{sub}60 fullerite thin films are presented. The films were prepared by vacuum thermal evaporation and deposition on a NaCl substrate. The temperature of the substrates was held between the room temperature and 473K. The films were investigated in a transmission electron microscope at accelerating potential of 100 kV and by X-ray method. The dark field images of some individual fullerite particles and especially grains of continuous thin films revealed the stacking faults or twin boundaries. The X-ray diffraction patterns of the fullerite films differ by the extremely diffuse reflections and by presence of some weak reflection near (111) which can be attributed to hexagonal close-packed (h. c. p.) fullerite. For more detailed estimation of fullerite films structure Full Profile Rietveld analysis version 3.5 was used. The best coincidence of the experimental and theoretical diffraction profiles was achieved for such structural parameters: the correlation of f.c.c. (a = 1,4117 nm) and h.c.p. (a=0,9756 nm, c=1,7084 nm) phases --46/54 mass%. The electrochemical study has shown that in case of Pd-activated fullerite film the well-marked hysteresis was observed, that confirms the formation of some hydride phases on the surface of C{sub}60 film.