The impact of dissolved reactive gases on platinum dissolution in acidic media (2023)

Section snippets

Experimental section

The measurements are performed using a micro-electrochemical scanning flow cell (SFC) directly connected to an inductively coupled plasma mass spectrometer (NexION 300×), so that the electrochemical and spectrometric signals are recorded in parallel. The coupled system was described in more detail in our previous studies [1], [4]. The hardware components are controlled by an in-house programmed LabVIEW application [5] and the experimental results are presented on synchronized time scales. A

Results and discussion

While our previous conclusions on platinum dissolution were predominantly based on the analysis of the interaction between the Pt surface and the electrolyte, the influence of the reactive gases like hydrogen, oxygen and carbon-monoxide on Pt dissolution was so far not considered. Taking into consideration that the adsorption of these gases can however be competitive with the adsorption of oxygen containing species originating from the solvent itself, and thus potentially interfere with


We present a compact study on Pt dissolution during potential cycling in acidic electrolyte in the presence of various reactive gases. Argon, hydrogen and oxygen do not interfere with the fundamental processes of surface oxidation/reduction and thus the consequent dissolution. However, certain peculiarities are observed in the case of a CO saturated electrolyte, which provides additional important insights into the platinum dissolution mechanism. Adsorbed CO leads to a re-structuring of the Pt


We thank the BMBF (Kz: 033RC1101A) for the financial support.

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