Boron doping compounds

Other materials were also employed to construct electrodes for amperometric detection. For instance, a boron-doped diamond (BOD) electrode was used for amperometric detection of nitroaromatic explosives, organophosphate nerve agents, and phenols. The BOD electrode offers enhanced sensitivity, lower noise, negligible adsorption of organic compounds, and low sensitivity to oxygen [760], In addition, a copper particle-modified carbon composite electrode was used for amperometric detection of glucose in a PDMS chip [761]. 

Owing to its extraordinary chemical stability, diamond is a prospective electrode material for use in theoretical and applied electrochemistry. In this work studies performed during the last decade on boron-doped diamond electrochemistry are reviewed. Depending on the doping level, diamond exhibits properties either of a superwide-gap semiconductor or a semimetal. In the first case, electrochemical, photoelectrochemical and impedance-spectroscopy studies make the determination of properties of the semiconductor diamond possible. Among them are the resistivity, the acceptor concentration, the minority carrier diffusion length, the flat-band potential, electron phototransition energies, etc. In the second case, the metal-like diamond appears to be a corrosion-stable electrode that is efficient in the electrosyntheses (e.g., in the electroreduction of hard to reduce compounds) and electroanalysis. Kinetic characteristics of many outer-sphere... 

In order to realize junction 4ight-emitting diodes (LEDs) having the same structure as that of practical III-V compound semiconductor LEDs, we must achieve n- and p-type conductivity control. The phosphorus and boron doping, which is known to be effective for obtaining high-conductivity n- and p-type a-Si H, respectively, seems to be less effective for the... 

Polcaro, A. M., Vacca, A., Palmas, S. and Mascia, M. (2003) Electrochemical treatment of wastewater containing phenolic compounds Oxidation at boron-doped diamond electrodes. J. Appl. 

Pignatello, J.J. (1992) Dark and photoassisted iron (3+)-catalyzed degradation of chlorophenoxy herbicides by hydrogen peroxide. Environ. Sci. Technol. 26, 944-951 Polcaro, A.M., Mascia, M, Palmas, S. and Vacca, A. (2002) Electrochemical oxidation of phenolic and other organic compounds at boron doped diamond electrodes for wastewater treatment Effect of mass transfer. Ann. Chim. 93, 967-976... 

In principle, oxidation could occur simultaneously during a HDH (reduction) reaction. For example any de-halogenated compounds could be oxidised to C02 in the anode compartment. Thus in the case of pentachlorophenol the phenol produced by the HDH could be oxidised at a suitable anode (e.g. boron-doped diamond) to C02 ... 

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. 

The past two decades have seen the establishment of a very extensive literature on the application of boron-doped diamond electrodes for the decoloration and the removal of COD and TOC from effluents, the disinfection and quality improvement of water, and the complete oxidation of particular organic molecules [26, 38, 39, 71-75]. There can be no doubt that boron-doped diamond anodes allow the effective killing of microorganisms and the complete oxidation of a wide range of organic compounds to carbon dioxide (and other inorganic fragments). Both direct and indirect mechanisms have been invoked. The direct mechanisms involve electron transfer and oxidation via weakly adsorbed OH radicals, while the indirect mechanisms have seen a role for solution-free OH radicals, ozone, sulfate radicals, or chlorine compounds if suitable anions are present or added. Indirect routes via ozone [20, 21] and sulfate radicals [40, 74, 76-78] can, of course, become dominant with appropriate selection of the conditions. This literature has been extensively reviewed and the interested reader is referred to these reviews [26, 38, 39, 71-75]. 

Boron-doped diamond (BDD) is an interesting electrode material because of the wide potential range even in aqueous electrolyte. One of the possible applications is the use for wastewater treatment. At the positive potential limit, OH-radicals are formed which oxidize nearly every organic compound. DBMS is used here because... 

More recently, boron-doped diamond (BDD) electrodes have been extensively studied for the oxidation of both organic compounds and ammonia contained in landfill leachates [11, 12]. Several technological properties of BDD electrodes make this material an outstanding candidate for the treatment of landfill leachates (i) an inert surface with low adsorption properties... 

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