کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
179060 | 459334 | 2014 | 5 صفحه PDF | دانلود رایگان |
• Impact of reactive gases on Pt dissolution monitored by in-situ mass spectrometry.
• Pt dissolution in presence of O2 and H2 is comparable with the behaviour in Ar-saturated solutions.
• CO bulk oxidation suppresses the anodic dissolution and promotes overall Pt amounts.
Long-term stability of platinum catalysts still represents a massive challenge for applications in energy conversion devices like fuel cells. One of the key issues is platinum dissolution during potential perturbations in corrosive acidic environment. In order to improve the understanding on the complex dissolution processes at the electrode–electrolyte interface, we have thoroughly investigated polycrystalline platinum by utilizing online mass spectrometry in parallel to electrochemical experiments. In particular, the focus of the current study is the impact of dissolved, reactive gases on platinum dissolution in perchloric acid. While oxygen and hydrogen do not alter the behaviour compared to an electrolyte saturated with an inert gas, carbon monoxide introduces substantial alterations. Anodic dissolution during the oxide formation is suppressed in the case of CO bulk oxidation, however, upon the reduction of the surface in the negative going scan the amount of dissolved Pt is enhanced with a factor of three to four due to blockage of the reduced surface sites for re-deposition.
Journal: Electrochemistry Communications - Volume 40, March 2014, Pages 49–53