Structural properties of silicon oxycarbide powders obtained by SOL-GEL method

摘要

This study is a characterisation of materials prepared from a mixture of substituted alkoxysilanes, typically R_xSi(OR')_(4-x) where x chemical bounds 1 or 2, by the sol-gel method. The system is based on two prectursors with different content of Si-O and Si-C bonds: methodyldiethoxysilane HSi(OEt)_2CH_3 (MDES) and triethoyxsilane HSi(OEt)_3 (TREOS) respectively. This selection was suggested because the composition of the glass after pyrolysis can easily be controlled by the ratio of the two precursors in the initial mixture. The alkoxides mixture leads to a polymer which interconnected units of two or three Si-O bonds in the forming gel labelled D~H or T~H, respectively.