Synthesis of Polyceriborosilazane via Substitution and Polymerization and Pyrolysis to SiBCN(Ce) Ceramics

Abstract: The introduction of metal atoms into SiBCN network allows the development of novel high temperature ceramics and functional ceramics. In this work, cerium (Ce) containing polyborosilazane (PBSZ) is synthesized through substitution and polymerization reactions. Ce atoms are incorporated into PBSZ through the lithium replacement of H in PBSZ followed by Ce replacement of lithium. The chemical structure of the PBSZ and as-synthesized Li containing PBSZ are analyzed by Fourier transform infrared (FTIR) shows that the bands at 598 and 1183 cm-1 which can be assigned to Li-N and Si-N-Li stretching. It is suggested that lithium is incorporated into PBSZ. PBSZCe is transformed into SiBCNCe ceramic by pyrolysed in argon. Scanning electron microscope shows that the SiBCNCe ceramics are porous on the surface and corallike in the section. The chemical bondings of SiBCNCe ceramics are BN, the BN, SiC and Si3N4 characterized by X-ray photoelectron spectroscopy.