Abstract |
The performance of electrodes, prepared from amorphous CoxByHz
nanoparticles without additives, in 20% KOH solution was tested by
means of cyclic voltammetry and chronopotentiometry. Peaks,
assigned to hydrogen adsorption and desorption, are observed in the
cyclic voltammograms. After charging, hydrogen atoms occupy
diferent types of sites in the substrate, from which
electrochemical desorption occurs. An increase in hydrogen content
as a result of repeated cycling was established. Discharge capacity
of the electrodes, estimated from the chronopotentiometric
discharge curves obtained, is about 250mAh g-1. The observed
changes in hydrogen and boron content, due to electrochemical
treatment, indicate that the electrode material is an active
participant in the whole electrochemical process. Hypotheses for
the reaction mechanism are proposed. Keywords: CoxByHz
nanoparticles, borohydride reduction, metal hydride electrodes
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