Electroreduction of boron in chloride-fluoride melts

Electroreduction of the BF4- complexes is studied on the silver and glassy-carbon electrodes in the NaCl-KCl and NaCl-KCl-NaF melts. The boron complexes are shown to reduce in these melts via a single, irreversible stage involving three electrons. The process of cathodic boron incorporation in the glassy-carbon electrode is found to be accompanied by formation of the B4C compound. The transfer and diffusion coefficients for boron complexes are measured. The diffusion coefficients obtained when using the silver and glassy-carbon electrodes are shown to be close, because of an insignificant contribution made by the discharge of boron complexes into the overall process.