SiC/C纳米复合材料的制备与性能表征

Preparation and Characterization of SiC/C Nano-composites

在Ar气的保护下,以微米级的石墨粉和Si粉为原料,H2为活性气体,通过直流电弧等离子体法原位合成SiC/C纳米复合材料.采用XRD,Raman和红外光谱分析产物的成分;应用SEM和TEM观察产物的形貌和微结构;使用紫外可见漫反射光谱仪和紫外可见分光光度计分别测试了产物的光吸收性质和对亚甲基兰的光催化降解性能.结果表明：产物是由占主相的β-SiC和少量的C组分构成的SiC/C球状复合物;包覆的C壳层厚度为60nm,核层是平均粒径50nm的SiC颗粒,复合体的尺寸约为0.5～1μm;带隙为2.35eV,此复合材料具有较好的电子迁移性能和一定的光催化性能.

Using micrometer-sized graphite powder and Si powder as raw material, SiC/C nano-com- posites were in-situ synthesized by direct current arcdischarge plasma method with H2 as reactive gas under the Ar atmosphere. The components of the obtained product were characterized by XRD, Raman and IR. The morphology and microstructure of the sample were observed by SEM and TEM. Op- tical absorption properties and photoeatalytic ability in decomposition of methylene blue were tested respectively by UV-visihle reflection spectrometer and UV-VIS spectrophotometer. The results indicate that the assynthesized products are globular composites of SiC/C consisting of β-SiC as main phase and a small amount of C;The average diameter of the composite is about 0.5μm, of which the thickness of C shell is 60 nm and the inner is SiC particles with average diameter of 50 nm. The band gap of the as-formed composites is 2.35eV and which exhibit high electron mobility and certain photo-catalytic ability.