Thermodynamic Analysis of Synthetic Potentialities of the nSiC + SiO2 Starting System: SiC Gas-Phase Transport via Si(g) and CO(g)

The major objective of our studies was the thermodynamic analysis of the nSiС+SiO2 system and revealing potentialities for the implementation of the SiC gas-phase transport conditions. As a result of thermodynamic scanning of the chemical activity of nSiС+SiO2 system the conditions for implementing the SiC gas-phase transport were found out within a wide temperature range. It was found out that the basic process in the gas-phase transport of silicon carbide is: SiCs + SiOg→ 2Sig + СОg SiC evaporation at T2 2Sig + СОg → SiCnanowhiskers + SiOg SiC deposition at T1 Sequential evaporation and deposition of silicon carbide result in the growth of SiC crystals from a gas phase. The processes of SiC gas-phase transport and deposition were experimentally realized. Synthesized were SiC nanocrystals over 300 μm long, ~ 300 nm in diameter that forms a three-dimensional subskeleton inside the carbon skeleton.