Synthesis and characterization of SiC nano powder with low residual carbon processed by sol–gel method

Abstract

Silicon carbide nanopowders and nanowhiskers were synthesized using phenolic resin and silicon alkoxide as precursors through sol–gel process with atomic ratio of C/Si=1.8 in water–solvent–catalyst–dispersant system. The effects of soaking time on free carbon content and synthesized β-SiC particle morphology were evaluated at 1500°C. The synthesis process of β-SiC nanopowders was completed at 1500°C after 1h while β-SiC nanowhiskers were heterogeneously nucleated and grown from obtained nanopowders after 2–3h. The detected free carbon content in whiskers was less than 1% after 3h.