作者：Jing Li1,2 ● Hongli Liu* 1,2 ● Yiting Zhang1,2 ● Yajing Li1,2 ● Dongli Qi1,2 ● Zhong Chen3
關(guān)鍵字：Polymer-derived ceramics, Fe-doped, Flower-like. Infrared extinction
論文來源：期刊
具體來源：Journal of Sol-Gel Science and Technology
發(fā)表時(shí)間：2020年
Nonoxide ceramics microspheres with multiple compositions are attractive for wide applications especially in thermal insulation science. The flower-like Fe-doped Si–C–N ceramic microspheres with the average size of about 1 μm were fabricated from polyvinylsilazane and ferrocene precursor through polymer-derived ceramics technology combined with emulsion polymerization method. The properties of the resultant microspheres were characterized by FTIR, SEM-EDX, VSM, TGA, and XRD. The morphology and size of the microspheres could be tuned by changing of ferrocene content, cross-linking time, and pyrolysis temperature. The ceramic microspheres were estimated to be composed of SiC/Si3N4 and α-Fe/Fe2O3 crystal phase, and the folding sheets on the surface induced the flower-like morphology due to phase separation and crystal rearrangement. The effective extinction coefficient of silica aerogels opacified with 10 wt% of Fe-doped Si–C–N microspheres increased with rising pyrolysis temperature, the maximum value of e* reached 27.5 cm2/g at 1300 °C. Moreover, the microspheres showed weak room temperatures ferromagnetism, which was facilitated to alignment infabrication and recycle, make them an ideal candidate for aerogels in infrared shielding application.