Synthesis of highly dispersed silicon carbide powders by a solvothermal-assisted sol-gel process

摘要

Highly dispersed silicon carbide powders were prepared by a solvothermal-assisted sol-gel process with tetraethyl orthosilicate and phenolic resin as starting materials and carbothermal reduction reactions at a relatively low temperature (1400-1600 A degrees C). Investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscope and the nitrogen adsorption-desorption isotherm measurements, the obtained SiC powders had an average crystallite size of 200 nm and high specific surfaces areas of 149 m(2)/g. Besides, mechanism for preparation of highly dispersed SiC powders was proposed.