Fibers, boron-doped

Zinc—bromine storage batteries (qv) are under development as load-leveling devices in electric utilities (64). Photovoltaic batteries have been made of selenium or boron doped with bromine. Graphite fibers and certain polymers can be made electrically conductive by being doped with bromine. Bromine is used in quartz—haUde light bulbs. Bromine is used to etch aluminum, copper, and semi-conductors. Bromine and its salts are known to recover gold and other precious metals from their ores. Bromine can be used to desulfurize fine coal (see Coal conversion processes). Table 5 shows estimates of the primary uses of bromine. 

Figure 9. Discharge curves of (a) normal and (b) boron doped Melblon carbon fiber at 1, 2, and 6 mA/cm2.

Nishimura K, Kim YA, Matushita T, Hayashi T, Endo M, Dresselhaus MS. Structural characterization of boron-doped submicron vapor-grown carbon fibers and their anode performance. J Mater Res 2000 15 1303-1313. 

It has been shown that substituted boron atoms in the carbon lattice can accelerate the graphitization and suppress the oxidation of carbon materials [149-152]. Furtha-, electromagnetic properties of graphite are reported to be strongly affected by a small amount of substituted boron [153]. An example of application is the use of boron-doped carbon fibers, BCx, as a reinforcement of C-C composites in the aerospace industry, as an alternative to C-C structural materials that oxidizes at temperatures in excess of673 K [154—155]. 

A simple cell using RVC has been described in Ref. [94]. A bare and gold-plated RVC electrode has been used in the study of microperoxidase [152], A bundle of cylindrical carbon fiber microelectrodes was used to monitor the catalytic reaction between ferrocyanide and ascorbic acid using the open-drcuit kinetic method [153]. While boron-doped diamond has shown great promise as a new electrode material, its transparency has not yet been exploited in UV-vis spectroelectrochemistry [154],... 

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]...

Among all carbon-based materials, certainly the most used is the glassy carbon although many other derivatives such as carbon pastes with graphite, earbon fibers, carbon nanotubes, fullerenes or even boron-doped diamond are also currently available. A brief description regarding some of those above-cited will now take place. 

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