Mesoporous silicon carbide (SiC) nanostructures were synthesized by magnesiothermic reduction of carbon–silica (C/SiO₂) nanocomposites at a low temperature of 700 °C by using furfuryl alcohol as the carbon source. The phase, morphology, and structure of the samples were characterized by a combination of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, X-ray photoelectron spectroscopy, thermogravimetric analysis, and N₂ adsorption. The starting C/SiO₂ composites exhibited an interpenetrating network and the resulting SiC preserved the mesoporous properties of the original templates. The SiC products were of β-SiC phase and showed a high surface area of 786 m²/g. The reaction mechanism and role of intermediate species (Mg₂Si) were explored in detail. Furthermore, the resulting β-SiC exhibits remarkable electromagnetic wave absorption performance with a minimum reflection loss of −17.2 dB and reflection loss bandwidth less than −10 dB of 3.7 GHz.

中文翻译：

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C / SiO ₂纳米复合材料的低温转变为高表面积的β-SiC

以糠醇为碳源，通过在700°C的低温下对碳-二氧化硅（C / SiO ₂）纳米复合材料进行镁热还原，合成了介孔碳化硅（SiC）纳米结构。通过X射线衍射，扫描电子显微镜，透射电子显微镜，傅立叶变换红外光谱，X射线光电子能谱，热重分析和N ₂吸附的组合来表征样品的相，形态和结构。起始的C / SiO ₂复合材料表现出互穿网络，所得的SiC保留了原始模板的介孔性能。SiC产物为β-SiC相，显示出786 m ²的高表面积/G。详细探讨了中间物种（Mg ₂ Si）的反应机理和作用。此外，所得的β-SiC表现出显着的电磁波吸收性能，最小反射损耗为-17.2dB，反射损耗带宽小于3.7GHz的-10dB。