Borohydride electro-oxidation on Pt single crystal electrodes

• Borohydride oxidation reaction is a structure sensitive reaction.
• The activity for low index planes at low potential is Pt(110) > Pt(100) > Pt(111).
• OH adsorption and oxide formation affect the reactivity.

The borohydride oxidation reaction on platinum single-crystal electrodes has been studied in sodium hydroxide solution using static and rotating conditions. The results show that borohydride electro-oxidation is a structure sensitive process on Pt surfaces. Significant changes in the measured currents are observed at low potentials. In this region, the Pt(111) electrode exhibits the lowest activity, whereas the highest currents are measured for the Pt(110) electrode. The behavior of the different electrodes is discussed taking as reference the observed behavior on the blank electrolyte and the possible formation of weakly adsorbed intermediates.