粘胶基碳纤维表面结构的STM研究

Scanning tunneling microscopy study of rayon-based carbon fiber surfaces

本文建立了用具有原子级分辨能力的扫描隧道显微镜 (STM)研究粘胶基碳纤维 (RCF)表面结构的方法。在较大尺度的STM图像上 ,RCF表面显得很粗糙 ,“峰”和“谷”的特征非常明显。增大放大率时 ,发现了约10nm宽的条状结构 ,其排列与纤维轴成一定角度 (45°～ 90°)。首次获得了RCF原子级的STM图像 ,在原子级尺度上 ,其原子排列并不规则 ,相邻原子间距为 0 .14 2nm ,最近六元环中心的距离是 0 .2 5 3nm。与高定向降解石墨 (HOPG)

The scanning tunneling microscope(STM),due to its atomic resolution,has been chosen as an extremely valuable tool to study the surfaces of carbon fibers.This work is an attempt to investigate the surface nature of rayon based carbon fibers(RCF) with the help of STM.At large scales,the RCF exhibits some rugosities with 'peaks' and 'valleys'.As the magnification is increased,the surfaces are characterized by the stripe form crystallite stackings with the diameter of about 10nm aligned with an angle between 45°～90° to fiber axis.Remarkable results are obtained at atomic resolution scales.Graphite like structure on the surface of RCF examined has been observed firstly.Compared with highly oriented pyrolytic graphite(HOPG),the distance between two adjacent carbon atoms of RCF is 0.142nm,while the distance between the closest centers of hexagonal carbon rings is 0.253nm,revealing the carbon hexagon structure of RCF is deformed graphene.