Straightforward synthesis and molecular structure optimization of novel SiZrBOC ceramic precursor via sol-gel and solvothermal approach

摘要

A novel SiZrBOC ceramic precursor polymer was synthesized directly using triethoxymethylsilane, boric acid and zirconium oxychloride hydrate via sol-gel and solvothermal method and the ceramic precursor followed by pyrolysis at 1000-1400 degrees C under argon atmosphere. The chemical composition, morphological change and crystallization behavior of SiZrBOC ceramics were carefully studied by means of FT-IR, XPS, SEM, and X-ray diffraction analysis. The degree of graphitization of products are analyzed by Raman spectroscopy. It proved that the content of sp(2) carbon in ceramic was low and it can be judged that the ability of boron to promote the crystallization of free carbon is less than the ability of the oxygen-containing compound of zirconium to limit the crystallization of free carbon. The experimental results showed that the effect of monomer feed ratio have a direct impact on the SiZrBOC microstructure, thermal stability and ceramic residue, an 86.5% ceramic yield can be achieved after molecular structure optimization. The SiZrBOC ceramics had been found to exhibit remarkably high temperature stability at 1400 degrees C in air atmosphere.