Assessment of Platinum Dissolution from a Pt/C Fuel Cell Catalyst: An Electrochemical Quartz Crystal Microbalance Study

作者:Ofstad Axel B*; Thomassen Magnus S; de la Fuente Jose L Gomez; Seland Frode; Moller Holst Steffen; Sunde Svein
来源:Journal of the Electrochemical Society, 2010, 157(5): B621-B627.
DOI:10.1149/1.3327890

摘要

The stability of different types of platinum surfaces in the presence of chloride was evaluated by applying a potential of 1.2 V vs reversible hydrogen electrode while the associated mass change in the Pt electrode was monitored with an electrochemical quartz crystal microbalance. The platinum metal surfaces based on the particles and films show a large difference toward dissolution when exposed to small amounts of chloride. While an electrodeposited platinum metal film showed no degradation in a sulfuric acid solution containing 10 ppm of chloride, an electrode made from a fuel cell catalyst (50 wt % Pt/C) lost 10% of its platinum content over a 24 h period when exposed to a sulfuric acid solution containing 10 ppm of chloride. At a chloride concentration of 20 ppm, the onset potential of the Pt oxide formation increased similar to 200 mV compared to an electrode in a chloride-free solution. The degradation of nanoparticles thus appears to be much more significant than for the electrodeposited platinum electrodes.

  • 出版日期2010