Studies of the Surface of SiC Nanometer Powder
YANG Xiu-Chun; HAN Gao-Rong; LI Fu-Shen; ZHOU Guo-Zhi(Department of Physical Chemistry, Science and Technology University Beijing Beijing 100082 China)(Department of Materials Science and Engineering, Zhejiang Unversity Hangzhou 310027 Chine)
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.