Raman spectra and staging of intercalated graphite fibers

✍ Scribed by P. Kwizera; M.S. Dresselhaus; G. Dresselhaus

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 883 KB
• Volume: 21
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(83)90167-7

✦ Synopsis

Raman spectra of graphite fibers intercalated with K, Rb and Cs are reported. X-Ray diffraction is used to characterize the fibers with respect to staging. We report results mainly for GY70, a highly graphitic commercially available fiber, which is polyacrylonitrile (PAN) based, and some results on UC4104B, a pitch-based fiber. These two fibers have different structures; ideally the GY70 consists of graphite layers parallel to the fiber surface, while UC4104B has graphite planes perpendicular to the surface. X-Ray diffraction, using the Debye-Scherrer method, shows that these fibers stage, though compounds of mixed stages are generally obtained. Our Raman results, which are sensitive to the staging within an optical skin depth, show for the alakli metal donor-intercalated fibers the %Ocm-' line characteristic of stage 1 compounds, the Ezgz bounding layer mode characteristic of stage 2, as well as the interior and bounding layer splitting of the Ezs~ mode, observed in high stage intercalated graphite. In addition, a Raman line near 1355 cm-' is observed, characteristic of less ordered graphites.