Using Cavity Microelectrodes for Electrochemical Noise Studies of Oxygen‐Evolving Catalysts

• DOI: 10.1002/cssc.201402855
• Publication Date: 2014-12-29T19:56:24Z
• Authors: Rosalba A. Rincón; Alberto Battistel; Edgar Ventosa; Xingxing Chen; Michaela Nebel; Wolfgang Schuhmann
• Keywords: Overpotential; Oxygen evolution; Electrochemical noise; Ohmic contact

Abstract Cavity microelectrodes were used as a binder‐free platform to evaluate oxygen evolution reaction (OER) electrocatalysts with respect gas bubble formation and departure. Electrochemical noise measurements performed by using RuO 2 benchmark catalyst the perovskite La 0.58 Sr 0.4 Fe 0.8 Co 0.2 O 3 non‐noble metal OER lower intrinsic conductivity. Changes in current during originate from variations electrolyte resistance of phase partial coverage active area. Fluctuations observed conductance transients establish contribution ohmic overpotential determine characteristic frequency evolution. The proposed quantitative determination growth departure opens up route for rational interface design considering main contributing factor overall electrocatalytic activity at high densities.