Boron-doped graphite

Chemical erosion can be suppressed by doping with substitutional elements such as boron. This is demonstrated in Fig. 14 [47] which shows data for undoped pyrolitic graphite and several grades of boron doped graphite. The mechanism responsible for this suppression may include the reduced chemical activity of the boronized material, as demonstrated by the increased oxidation resistance of B doped carbons [48] or the suppressed diffusion caused by the interstitial trapping at boron sites. 

Fig. 14. Chemical yield as a function of temperature for boron doped graphites.

Bindra, C. Nalimova, V. A., and J. E. Fischer. 1998. In-plane structure and thermal (in)stability of LiC218 based on boron-doped graphite. Mol. Cryst. Liq. Cryst. 310 19-25. 

Since the initial proposals by Coughlin and Mattson, many published papers have attempted to elucidate the most appropriate mechanism to explain the adsorption of phenolic compounds and of aromatic compounds in general on carbon materials. Perhaps the first experimental evidence of the Tr-ir dispersion interaction mechanism was provided by Mahajan and coworkers [19] in their study of phenol adsorption on graphite and boron-doped graphite samples. They reported that the presence of substitutional boron in the lattice of polycrystalhne graphite, which removes ir-electrons from the solid, results in a lowering of the phenol uptake from water. 

Kouvetakis J., McElfresh M.W and Beach D.B. Chemical Vapor Deposition of Highly Conductive Boron-Doped Graphite from Triphenyl Boron // Carbon. 1994. V. 32. No 6. P. 1129-1132. 

Fig. 8 High resolution Bjg spectra by XPS of two different types of boron-doped graphite and mesophase pitch carbon fibers. Reproduced from Ref. [6]...

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