Effect of process parameters on the production of nanocrystalline silicon carbide from water glass

• Published in: Ceramics international 2008-03, Vol.34 (2), p.391-395
• Main Authors: Pan, Shunlong, Zhang, Jingjie, Yang, Yanfeng, Song, Guangzhi
• Format: Article
• Language: English
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Carbothermal reduction; Ceramic industries; Chemical industry and chemicals; Cross-disciplinary physics: materials science; rheology; D. SiC; Exact sciences and technology; Materials science; Nanopowders; Nanoscale materials and structures: fabrication and characterization; Physics; Structural ceramics; Technical ceramics; Water glass
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2006.10.019

Nanocrystalline silicon carbide was synthesized from the precursor prepared by spray drying slurry of water glass and carbon black. The effect of process parameters, such as reaction temperature, reaction time and carbon content, on phase evolution, crystallite size and specific surface of the resulting samples were characterized by XRD, SEM and BET. The results show the powder produced in this process has a very fine crystallite size and high specific area and the reaction can be completed at 1550 °C for 2 h when the C/Si ratio is 5 or larger. In addition, the powder is of high purity, because sodium oxide in the precursor can be eliminated by the escape of sodium at high temperature. It is a simple and cost-efficient method to synthesize nanocrystalline silicon carbide using cheap and abundant water glass as silicon source.