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使用高纯SnO2粉和石墨粉混合物作为锡催化剂的来源, 硅片作为硅的来源和产物生长的基底, 用化学气相沉积法在硅片上准备了有序排列的氧化硅纳米线组成的微米结构, 用扫描电子显微镜(SEM)、X--射线能谱仪(EDX)、透射电子显微镜(TEM)和选区电子衍射谱图(SAED)对其进行了表征。结果表明: 直径为5--15 μ m, 长度达到50--100 μm的微米结构由紧密排列的非晶氧化硅纳米线组成, 氧化硅纳米线的直径为100--200 nm, 长度达到50--100 μm。根据对其生长过程的分析, 锡催化生长表现出不同于传统的VLS机制, 一颗锡催化剂液滴能同时诱导多根纳米线的生长。根据室温下的光致发光谱分析, 非晶氧化硅纳米线在395 nm(3.14 eV)处有一强峰, 激发波长为260 nm(4.77 eV)。

A novel micro–structure which consists of highly aligned and closely packed silica nanowires has been synthesized by using chemical vapor deposition (CVD) process. The tin droplets were supplied by carbothermal reduction of SnO2 powders as catalyst, and the source and substrate of the growth of silica nanowires was silicon wafers. This novel micro–structure was investigated by the scanning electron microscopy (SEM), energy–dispersive X–ray spectroscopy (EDX), transmission electron microscopy (TEM) and selected area electron diffraction (SAED) analyses. It was found that the diameters of the novel micro–structures and the amorphous silica nanowires are 5–15 μm and 100–200 nm with the same length of 50–100 μm, respectively. Finally, it is of interest to note that, each tin droplet can simultaneously catalyze the growth of several silica nanowires, which is quite different from the conventional vapor–liquid–solid process, and the silica nanowires tend to grow batch by batch. The PL spectra of the SiO2 nanowires showe a strong light at 395nm (3.14 eV) under excitation at 260 nm (4.77 eV).