Defects in graphite

P. A. Thrower, Study of defects in graphite by transmission electron microscopy, Chem. Phys. Carbon, vol. 5, pp. 217-319,1969. 

Electron Microscopy of Reactivity Changes near Lattice Defects in Graphite, G. R. Hennig... 

The Study of Defects in Graphite by Transmission Electron Microscopy, P. A. 

S. Letardi, M. Celino, E. Cleri and V. Rosato, Atomic hydrogen adsorption on a Stone-Wales defect in graphite . Surface Science, 496, 33 (2002). 

Cabrera-Sanfelix, R, Darling, G. R. (2007). Dissociative adsorption of water at vacancy defects in graphite. The Journal of Physical Chemistry C, 111,... 

The third term in Eq. 7, K, is the contribution to the basal plane thermal resistance due to defect scattering. Neutron irradiation causes various types of defects to be produced depending on the irradiation temperature. These defects are very effective in scattering phonons, even at flux levels which would be considered modest for most nuclear applications, and quickly dominate the other terms in Eq. 7. Several types of in-adiation-induced defects have been identified in graphite. For irradiation temperatures lower than 650°C, simple point defects in the form of vacancies or interstitials, along with small interstitial clusters, are the predominant defects. Moreover, at an irradiation temperatui-e near 150°C [17] the defect which dominates the thermal resistance is the lattice vacancy. 

Thrower, P.A. and Mayer, R.M., Review Article Point defects and self-diffusion in graphite, Phys. Stat. Sol. (a), 1978, 47, 11 37. 

Considering all the spectra from nested tubule samples first, it is clear from Table 1 that the data from four different research groups are in reasonable agreement. The spectral features identified with tubules appear very similar to that of graphite with sample-dependent variation in the intensity in the D (disorder-induced) band near 1350 cm" and also in the second-order features associated with the D-band (i.e., 2 X D <= 2722 cm ) and -f- D 2950 cm . Sample-dependent D-band scattering may stem from the relative admixture of nanoparticles and nanotubes, or defects in the nanotube wall. 

The actual utility of this discovery depends on the ability to go from hosts consisting of expensive, highly oriented, pyrolytic graphite to hosts composed of cheap graphite powders or fibers. Care must be taken on intercalation, because defects in such low-rank graphites may affect not only the intrinsic conductivity of the host (Z4) but may also serve as sites for oxidative reactions that may disrupt the host (Ell). 

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