摘要
本工作采用二甲基二氯硅烷和氢气为原料，在１１００～１４００℃温度条件下，通过化学气相沉积制备出了高纯、低氧含量的纳米ＳｉＣ粉体·实验结果指出，在１１００～１３００℃；制备得到的粉体颗粒由无定型相和β－ＳｉＣ微晶组成；而在１４００℃则粉体颗粒主要由β－ＳｉＣ微晶无序取向组成．随反应条件的改变，粉体平均粒径和β－ＳｉＣ微晶的平均尺寸分别在４０～７０ｎｍ和１．８～７．３ｎｍ范围内变化．同时，产物粉体的Ｃ／Ｓｉ摩尔比由低温１１００℃的０．５提高到１４００℃的１．０５．通过控制沉积条件如反应温度和反应物浓度，可以得到Ｃ／Ｓｉ摩尔比保持在０．９５～１．０５范围的、符合化学计量比的ＳｉＣ粉体．最后，用各种手段如化学分析，Ｘ射线衍射、透射电镜、高分辩电镜和红外吸收光谱等，对粉体性能和结构进行了表征．
Nanosized silicon carbide powders of high purity and low oxygen content were prepared by thermal chemical vapour deposition (CVD) of dimethydichlorosilane(DMS) at pyrolytic temperature 1100℃ to 1400℃. The nanosized silicon carbide particles prepared at 1400℃ consisted of small crystailites of β-SiCarranged randomly in the paticles. At lower pyrolytic temperature than 1300℃, the particles consisted of amorphous phase and β-type SiCcrystallite. The average particle size changed from 70 to 40 nm and the average size of β-SiC crystailite changed from 7.3 to 1.8nm depending on the Pyrolysis conditions.The C/Si molar ratios of the product powders changed from 0.5 to 1.07 with the CVD conditions. The near statistics of C/Si molar ratio of the product powders within 0.95 to 1.05 can be controlled by CVD conditions such as pyrolytic temperature and reactal concentration. Finally,The product powders were charaterized by chemical analysis, X-ray diffraction (XRD), electron microscopy (TEM and HREM) and infrared spectrum.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
1996年第3期441-447,共7页
Journal of Inorganic Materials
基金
"攀登计划"资助
