Nanosized SiC-based powders were prepared from selected liquid-phase organosilicon precursors by the
aerosol-assisted synthesis, the DC thermal plasma synthesis, and a combination of the two methods. The
two-stage aerosol-assisted synthesis method provides at the end conditions close to thermodynamic
equilibrium. The single-stage thermal plasma method is characterized by short particle residence times
in the reaction zone, which can lead to kinetically controlled products. The by-products and
final
nanopowders were characterized by powder XRD, infrared spectroscopy FT-IR, scanning electron
microscopy SEM, and 29Si MAS NMR spectroscopy. BET specific surface areas of the products were
determined by standard physical adsorption of nitrogen at 77 K. The major component in all synthesis
routes was found to be cubic silicon carbide b-SiC with average crystallite sizes ranging from a few to tens
of nanometers. In some cases, it was accompanied by free carbon, elemental silicon or silica
nanoparticles. The
final mesoporous b-SiC-based nanopowders have a potential as affordable catalyst
supports.
Nanosized SiC-based powders were prepared from selected liquid-phase organosilicon precursors by theaerosol-assisted synthesis, the DC thermal plasma synthesis, and a combination of the two methods. Thetwo-stage aerosol-assisted synthesis method provides at the end conditions close to thermodynamicequilibrium. The single-stage thermal plasma method is characterized by short particle residence timesin the reaction zone, which can lead to kinetically controlled products. The by-products andfinalnanopowders were characterized by powder XRD, infrared spectroscopy FT-IR, scanning electronmicroscopy SEM, and 29Si MAS NMR spectroscopy. BET specific surface areas of the products weredetermined by standard physical adsorption of nitrogen at 77 K. The major component in all synthesisroutes was found to be cubic silicon carbide b-SiC with average crystallite sizes ranging from a few to tensof nanometers. In some cases, it was accompanied by free carbon, elemental silicon or silicananoparticles. Thefinal mesoporous b-SiC-based nanopowders have a potential as affordable catalystsupports.
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