Graphite, intercalation compounds electrical conductivity

Elastic-inelastic collision model, Szilard-Chalmers reaction and, 1 269 Electrical conduction, in organic superconductors, 29 278-286 Electrical conductivity of chalcogenide halide compounds, 23 331 of Group IB, 23 337-339, 342, 346-349 photoelectric effects, 23 368, 410 semiconductors, 23 368, 390, 395-396, 400-402, 410-412 superconductors, 23 375-377 of graphite intercalation compounds, 23 290, 294, 309-310, 312, 317-318 Electric discharges arc type, 6 146-147 chemical reactions in, 6 189-191 chemical reactions in, 6 143-206... 

Graphite intercalation compounds have received widespread interest for two main reasons. First, intercalation results in compounds that have metallic conductivity. The electrical conductivity can approach that of copper metal and is highly anisotropic ratios of the conductivity in-plane to that along the c axis can be six orders of magiutude at room temperature. Secondly, graphite is a unique host lattice in that intercalation compounds can be formed with either electron donors or electron acceptors as guest species. 

The potassium donates an electron to the graphite (forming and the conductivity of the graphite increases. Graphite electron-acceptor intercalation compounds have also been made with NO3T CrOs, Br2, FeCls, and ASF5. Some of these compounds have electrical conductivity approaching that of aluminum (see Chapter 6). 

In lithium polymer batteries, one electrode is lithium foil, or in some cases another electrically conducting material such as graphite, and the other is a reversible intercalation compound as in liquid electrolyte lithium batteries. Compounds used as intercalation electrodes include LiCo02 and VeOis. The cell developed in the Anglo-Danish project, which ran from 1979 to 1995, was... 

Both of the potassium and polybromide intercalation compounds are good conductors of electricity. In the potassium inlercalam. the electrons in the conduction band can carry the current directly, as in a metal. In the compounds of graphite with polybromide. holes in the valence band conduct by the mechanism discussed previously for semiconductors (Chapter 7). 

T. E. Thompson, E. M. McCarron and N. Bartlett, The Electrical Conductivity of Graphite-AsFs Intercalation Compounds and Their Relationship to Other Graphite-MFe Salts, Synthetic Metals 3 (1981) 255-267. 

The electrical conductivity of carbon fibers is improved by intercalating donors (e.g., alkali metals) or acceptors (e.g., Br2, CI2, F2, chlorides or fluorides) between the carbon layers [1] [62]. These intercalation compounds are more easily formed in fibers which exhibit a highly ordered graphitic structure, i.e., the mesopitch based UHM carbon fibers. Some intercalation... 

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