Synthesis of photoluminescent Si-O-C(-H) ceramics from oxidation-cured polycarbosilane by hydrogen decarbonization

摘要

Polycarbosilane powder, formed by a desaturation process, was oxidation-cured at 180-340 C and pyrolyzed in a hydrogen atmosphere to obtain Si-O-C(-H) ceramics with low carbon contents. FT-IR was used to investigate the progress of the oxidation curing. Suitable curing conditions were found to be 240℃ for 20 h, and the powders obtained after the pyrolysis exhibited intense luminescence under UV irradiation. The chemical compositions of the resulting Si-O-C(-H) ceramics were close to the stoichiometric (SiO_2)-x(SiC)-y(H) compositions. The luminescence properties of these Si-O-C(-H) ceramics were analyzed by using time-resolved photoluminescence spectra.