(641e) The Role of Electrolytes in the Oxygen Evolution Reaction On IrO2

The oxygen evolution reaction (OER) is an energetically demanding and complex reaction that is critical to the implementation of energy storage techniques using water splitting.  Many works focus on searching for alternative catalysts, but a complete understanding of the electrode/adsorbate/electrolyte interaction is still unknown.  We have studied effects of the cation in the electrolyte on the kinetics of the oxygen evolution reaction in 0.1 molar aqueous alkali hydroxide electrolytes.  Iridium oxide (IrO₂₎ electrodes were prepared by electrodeposition onto gold and silver disk electrodes. The oxygen evolution activity was probed electrochemically using cyclic voltammetry and chronoamperometry.  We also observed potential dependent Raman spectra, which will be discussed. The highest activity was observed in KOH, followed by NaOH, and the lowest activities were observed in CsOH and LiOH.   This work illustrates that electrolyte engineering may be able to improve OER kinetics, and that the electrolyte plays a non-trivial role in OER performance.