Carbothermal synthesis of nanoparticulate silicon carbide in a self-contained protective atmosphere

Resumo

We report a process for the preparation of ultrafine silicon carbide powder in a self-contained protective atmosphere. The protective atmosphere is ensured by the silicon monoxide released during the carbothermal synthesis. A reactor design is proposed in which an excess silicon monoxide pressure is generated in order to prevent atmospheric oxygen from entering the reactor. The reactor makes it possible to synthesize silicon carbide in furnaces operating in air. The use of pure starting materials has allowed us to obtain silicon carbide nanofibers ≃ 100 nm in diameter, containing no more than 0.01 wt % impurities.