SiC纳米粉表面研究

Studies of the Surface of SiC Nanometer Powder

借助于TEM、IR和XPS分析；对新鲜的SiC纳米粉表面和不同存放时间及处理条件下的样品表面进行分析比较，发现新鲜的作品表面主要以物理吸附氧为主（78.25％），化合态氧为辅（21.75％），在空气中存放一个月后，O／Si比由新鲜样品表面的0.49上升至0.70表面发生氧化,继续存放一个月，O／Si比增至0．77；但表面氧化速度变缓,在潮湿空气中SiC纳米粉更易氧化．离子刻蚀分析表明，O主要分布在粉末表面．

The surface composition and bonding of a wide variety of SC nanometer poal.ders were characterized by TEM, IR and XPS. The results show that oxygen mainly exists in the form of physical adsorption for fresh SiC nanometer powder(adsorbed oxygen-78.25%, combined oxygen-21 .75%).When the powder was kept in air for a month, its O/Si mole ratio added from 0.49 to 0.70, when the powder was kept in air for two month, the O/Si mole ratio added to 0.77. The results showthat the oxidization of the powder becomes slower after a month. Oxidization of the poundder is easier in wet air than in dry air. Oxygen content decreases with increasing Ar+ sputtering time.and oxygen is mainly distributed over the surface of the powder.