HREM-STM Analyzes of Metal-C60 Interface Structures

由于C60晶体具有范德华力的粘聚力，材料的延展性和延展性都很差。为了弥补缺陷和充分利用C60，尝试制备了一种复合材料，用扫描隧道显微镜(STM)和高分辨电子显微镜(HREM)分析了所制备的复合材料的表面和界面结构，并成功地观察了在Au衬底和高取向热解石墨(HOPG)衬底上生长的C60薄膜的晶界结构。结果表明，C_(60)晶体易成核，并在石墨衬底上三维生长。在Au表面形成了稳定的多晶薄膜。薄膜由细小的晶粒组成。每一个颗粒都被紧密地包裹在胶片中。用高分辨电子显微镜分析了碳纤维/C60和Au/C60复合材料的界面精细结构。由于碳纤维和C60的晶格常数相差很大，在界面上没有发现任何外延结构。然而，一个连贯的平行结构的一些可能性仍然存在。在Au/C60复合材料中，在界面内或界面附近没有发现第三相析出的证据。结果表明，C60与Au是直接相连的，其表面是稳定的。

Since C60 crystal is cohesive of van der Waals force the material is so poor in malleability and ductility. In order to make up the defects and to make the best use of the C60, production of a composite material was attempted.Surface and interface structure of the produced composit materials were analized by scanning tunneling microscopy (STM) and high resolution electron microscopy (HREM).Grain boundary structure of a C60 thin film grown on both Au substrate and Highly Oriented Pyrolytic graphite (HOPG) substrate were successfuly observed. It was found that C60 crystal was easily nucleated and grew three dimensionally on graphite substrate. On the Au surface, stable polycrystalline thin film was formed. The film consisted of fine crystal grains. Each grains were closely packed in the film. The interface fine structure of carbon fiber/C60 and Au/C60composites were analyzed by HRTEM as well. Attributing to the large difference in lattice constant between carbon fiber and C60, any epitaxial structure was not found at the interface. However, some possibility of a coherent parallel structure still remains. At the Au/C60 composite, no evidence of third phase precipitaion was detected in or near the interface. It is concluded that C60 and Au are directly connected and its in the surface is stable.