Highly Porous SiOC Bulk Ceramics with Water Vapor Assisted Pyrolysis

摘要: Micro/mesoporous SiOC bulk ceramics with the highest surface area and narrowest pore size distribution were prepared by water-assisted pyrolysis of polysiloxane in argon atmosphere at controlled temperatures (1100°C–1400°C) followed etching hydrofluoric acid (HF) solution. Their behaviors, phase compositions, microstructures investigated DSC, FTIR, XRD, BET. The Si–O–Si bonds, SiO2-rich clusters, SiO2 nanocrystals pyrolyzed products act as pore-forming species could be etched away HF. Water injection time temperature have important effects on compositions porous ceramics, which a maximum-specific 2391.60 m2/g an average 2.87 nm. consist free carbon phase, silicon carbide, oxycarbide.