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.




Robert P. Devaty, David J. Larkin and Stephen E. Saddow




V.G. Sevastyanov et al., "Thermodynamic Analysis of Synthetic Potentialities of the nSiC + SiO2 Starting System: SiC Gas-Phase Transport via Si(g) and CO(g)", Materials Science Forum, Vols. 527-529, pp. 775-778, 2006


October 2006




[1] H-J. Choi and J-G. Lee: Continuous Synthesis of Silicon Carbide Whiskers, Journal of Materials Science, Vol. 30 (1995), p. (1982).

[2] Motojima and M. Hasegawa: Chemical Vapor Growth of β-SiC Whiskers From a Gas Mixture of Si2Cl6-CH4-H2-Ar, Journal of Crystal Growth, Vol. 87 (1988) p.311.


[3] H. Konishi, H. Tsuda, H. Mabuchi-Nakatani, K. Morii and K. Okamura: Silicon Carbide Nanofibers Synthesized Using Simple Chemical Vapor Reaction, Proceedings 5 th International Conference on High-Temperature Ceramic Matrix Composites (HTCMC 5), Seattle, (2004).

[4] W-S. Seo and K. Koumoto: Morphology and Stacking Faults of β-Silicon Carbide Whisker Synthesized by Carbothermal Reduction, Journal of American Ceramic Society, Vol. 83 (2000) p.2584.


[5] V.G. Sevastyanov, Yu.S. Ezhov, E.P. Simonenko and N.T. Kuznetsov: Thermodynamic analysis of the production of silicon carbide via silicon dioxide and carbon, Mater. Sci. Forum Vols. 457-460 (2004), p.59 Fig. 5. SiC nanofibre, TEM, 125000x.