在无催化剂条件下，以CH3SiCl3为前驱体，采用化学气相沉积技术(CVD)在C/C复合材料表面制备SiC纳米线。SEM 形貌表明：CVD 产物有大量数十微米长的纳米线，部分纳米线团聚呈球状，同时也发现类似带刺板栗外壳的短纳米线聚集，且纳米颗粒在其表面沉积等现象。XRD、拉曼光谱和红外光谱分析结果表明，此产物为典型的β-SiC。TEM形貌表明，此类纳米线的直径分布范围为10~100 nm，一些较细的纳米线可通过无定形SiC与较粗的纳米线结合在一起。在一根较粗SiC纳米线的无定形区域长出一根与其直径相近的分支，二者之间的夹角为70°，其与β-SiC晶体中[111]轴堆垛夹角一致。SAED和FFT结果表明，纳米线的生长轴线较多，在纳米线的竹节状区域存在大量堆垛层错和孪晶。边缘弯曲的SiC纳米线晶格面表明，螺旋位错生长为其主要的生长机制。%SiC nanowires were prepared on C/C composite surface without catalyst by chemical vapor deposition (CVD) using CH3SiCl3 as precursor. SEM images of the CVD-product reveal that some long nanowires have grown to tens of micrometers with some gathered as a ball. Some short nanowires agglomerate like chestnut shell with many thorns accompanied by some deposited nano-particles. XRD, Raman-spectrum and FTIR patterns indicate that the product is a typical β-SiC. TEM images show that the nanowires have a wide diameter range from 10 to 100 nm, and some thin nanowires are bonded to the thick one by amorphous CVD-SiC. A SiC branch generates from an amorphous section of a thick one with an angle of 70° between them, which is consistent with the [111] axis stacking angle of the crystal. SAED and fast Fourier transform (FFT) patterns reveal that the nanowires can grow along with different axes, and the bamboo-nodes section is full of stacking faults and twin crystal. The twisted SiC lattice planes reveal that the screw dislocation growth is the main mechanism for the CVD-SiC nanowires.
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