高温下铝碳耐火材料中多壁碳纳米管的结构演变  

Microstructure Evolution of Multi-walled Carbon Nanotubes in Al_2O_3-C Refractories at High Temperature

作　　者：廖宁[1] 李亚伟[1] 桑绍柏[1] 

机构地区：[1]武汉科技大学,省部共建耐火材料与冶金国家重点实验室,武汉430081

出　　处：《硅酸盐学报》2015年第3期251-260,共10页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(51372176);湖北省自然科学基金重点项目(2013CFA105)资助

摘　　要：利用X射线衍射仪、扫描电子显微镜及透射电子显微镜,研究了高温下以多壁碳纳米管为碳源、单质硅粉为添加剂的铝碳耐火材料中多壁碳纳米管的结构演变。结果表明:800℃时氧化导致部分碳纳米管管径减小;1 000℃处理后碳纳米管表面缺陷处形成碳化硅层,部分碳纳米管蚀变为碳化硅晶须;1 200及1 400℃处理后碳纳米管蚀变加剧,促进大量碳化硅晶须的生成。高温下铝碳材料中碳纳米管蚀变后主要以弯曲状Si C晶须存在,同时还观察到大量直杆状Si C晶须,其主要通过Si O与CO气相反应生长。The structure evolution of multi-walled carbon nanotubes(MWCNTs) in low-carbon Al2O3-C refractories with silicon additive was investigated. The structure evolution of MWCNTs at different coked temperatures was analyzed by X-ray diffraction, scanning electron microscopy and transmission electron microscopy, respectively. The results show that the diameter of MWCNTs decreases at 800℃ due to the oxidization of partial walls of MWCNTs. When the temperature is increased to 1 000 ℃, Si C coating is synthesized on the surface defects, and even a part of MWCNTs is transformed into Si C nano-whiskers. The transformation process is accelerated and the synthesis of considerable Si C whiskers is also stimulated when coked at 1 200 and 1 400 ℃. The morphology of Si C whiskers appears curved when MWCNTs convert. There are numerous straight Si C whiskers formed at high temperatures due to the vapor reaction of Si O and CO.

关 键 词：铝碳耐火材料 多壁碳纳米管 结构演变 

分 类 号：TQ175.1[化学工程—硅酸盐工业]