Fabrication and properties of lightweight SiOC fiber-based assembly aerogels with hierarchical pore structure

Here we report a novel aerogel material assembled by the electrospun SiOC fibers with a hierarchical pore structure. The fibrous aerogels were successfully fabricated by the gel-casting and freeze-drying method using the SiOC fibers as the matrix and the silica sols as the binders. The effect of the SiOC fiber content and the silica sol content on the properties of the samples were investigated. The SiOC fibrous aerogels after calcined at 1000 °C exhibited low densities of 46.87–128.48 mg/cm3, low thermal conductivities of 0.0302–0.0440 W/m K, high compressive strengths of 18–167 kPa and relatively high specific surface areas of 12.48–34.87 m2/g. Such unique fibrous aerogel materials are foreseen as the promising high-temperature insulators, absorbents and supports.