SYNTHESIS OF FULLERENE RHODIUM NANOCOMPOSITES VIA AEROSOL DECOMPOSITION

Highly disperse (20-100 nm) powders consisting of nanophase fullerenes and their nanocomposites with rhodium were generated by aerosol decomposition. Solutions of mixed fullerene extract (C60, C70) and [(1,5-COD)RhCl]2 in toluene were atomized and passed through a hot-wall reactor in N2 carrier gas where toluene evaporation and thermal decomposition of [(1,5-COD)-RhCl]2 to form Rh occurred. Nanocomposite particles were formed at a reactor temperature of 550-degrees-C which was sufficiently low to avoid C60 and Rh grain growth in each particle but sufficiently high to thermally decompose [(1,5-COD)RhCl]2. Transmission electron micrographs of pure fullerenes showed lattice fringes corresponding to the prominent d spacing of 8.2 angstrom in C60. TEM of the 50/50 wt % fullerene/Rh composite showed 3-5-nm Rh crystallites, consistent with the value of 4 nm calculated from X-ray diffraction peak broadening. Aerosol decomposition allows reasonable production rates of such nanophase materials at the laboratory scale and has the potential for scale up to larger levels.