Synthesis of nanoporous silicon carbide ceramics by thermal evaporation process

New nanoporous beta-SiC ceramics were synthesized by a simple thermal evaporation method with commercial silicon powder and activated carbon fragments. The results of scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy and X-ray diffraction indicated that the microstructure of the beta-SiC nanoporous ceramics was uniform and consistent with the pore size of 50-100 nm. The beta-SiC nanocrystal grains of 50-200 nm were accumulated together to form a nanopore network. The formation mechanism was attributed to a template synthesis process, in which activated carbon fragments were employed as the template and they reacted with vaporized silicon through a vapor-solid way. (C) 2010 Elsevier B.V. All rights reserved.