Active electrochemical interfaces stabilized through self-organized potential oscillations

Nogueira, Jéssica A.; Lopes, Pietro P.; Markovic, Nenad M.; Varela, Hamilton

doi:10.1016/j.elecom.2020.106853

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Active electrochemical interfaces stabilized through self-organized potential oscillations

Nogueira, Jéssica A.·Lopes, Pietro P.·Markovic, Nenad M.·Varela, Hamilton

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Abstract

Some electrochemical systems are known to have higher average efficiency when operated under an oscillatory regime. Given the compromise between activity and stability, the stability of electrochemical interfaces in a self-organized, oscillatory state must be taken into account. Here we evaluate the electro-oxidation of methanol and formic acid on platinum under regular and oscillatory conditions, and study the stability by following the Pt dissolution rates in situ with a stationary probe rotating disk electrode (SPRDE) coupled to an inductively coupled plasma mass spectrometer (ICP-MS). Generally speaking, as the electro-oxidation reaction proceeds, the platinum dissolution rate increases considerably. To guarantee Pt stability, the potential must be kept below 1.0 V vs. RHE. Interestingly, no dissolution is detectable when the electrode potential undergoes temporary self-organization, ensuring a stable and active interface.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Pt durability electrocatalysis formic acid methanol oscillations

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Nogueira, Jéssica A., Lopes, Pietro P., Markovic, Nenad M., Varela, Hamilton. 2020-10-22. Active electrochemical interfaces stabilized through self-organized potential oscillations. https://doi.org/10.1016/j.elecom.2020.106853

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