Characteristics of Copper Particles Supported on Various Types of Graphite Nanofibers

Abstract

We have used a variety of experimental techniques, including high-resolution transmission electron microscopy, X-ray diffraction, and adsorptive decomposition of N2O to examine the characteristics of copper particles dispersed on different types of graphite nanofiber supports. When copper was dispersed on the edge sites of graphite nanofibers the particles adopted a relatively thin faceted morphology; characteristics that are associated with the establishment of a strong metal−support interaction. This behavior is to be contrasted with that observed when the metal was supported on active carbon or the basal planes of graphite. In these cases, the particles tended to acquire a globular geometry typically encountered in systems were there are relatively weak interfacial forces between the metal and the support. Structural modeling of the arrangement of copper atoms on the prismatic and basal plane surfaces of graphite indicated that formation of preferred crystallite orientations occurred at certain support...