Effects of SiO2-forming additive on polysiloxane derived SiOC ceramics
Effects of SiO2-forming additive on polysiloxane derived SiOC ceramics
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DOI：
10.1016/j.micromeso.2018.02.034
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发表时间：
2018-08-01
影响因子：
5.2
通讯作者：
Lu, Kathy
中科院分区：
文献类型：
--
作者：
Erb, Donald;Lu, Kathy
新型超高表面积材料非常适合高温催化剂、电极和恶劣环境传感器等苛刻的应用。通过在聚硅氧烷基体中交联正硅酸四乙酯（TEOS），并在热解过程中引入水蒸气，研究了TEOS在聚硅氧烷陶化过程中原位转化为SiO2并掺入碳化硅（SiOC）陶瓷中的过程。研究了正晶硅对SiO2热物理性质、相发育和多孔SiO2的影响。交联聚合物中含有10 wt% TEOS的SiOC可产生最高的比表面积，约为2100 m(2)/g，平均孔径约为2 nm。比表面积和孔径分布与Voronoi图模拟和理想模型计算的理论结果相关。
Novel ultrahigh surface area materials are highly desired for demanding applications such as high temperature catalysts, electrodes, and harsh environment sensors. In-situ conversion of tetraethyl orthosilicate (TEOS) into SiO2 and its incorporation into silicon oxycarbide (SiOC) ceramics during polysiloxane ceramization are investigated by crosslinking TEOS within a polysiloxane matrix and introducing water vapor during pyrolysis. The effects of the TEOS-derived SiO2 on the thermophysical properties, phase development, and the resulting porous SiOC are investigated. The SiOC with 10 wt% TEOS within the crosslinked polymer creates the highest specific surface area of similar to 2100 m(2)/g with an average pore size of similar to 2 nm. The specific surface area and pore size distribution are correlated with the theoretical results from Voronoi diagram simulation and an idealized model calculation.