Electrochemical stability and postmortem studies of Pt/SiC catalysts for polymer electrolyte membrane fuel cells

ACS Appl Mater Interfaces. 2015 Mar 25;7(11):6153-61. doi: 10.1021/am508982d. Epub 2015 Mar 10.

Abstract

In the presented work, the electrochemical stability of platinized silicon carbide is studied. Postmortem transmission electron microscopy and X-ray photoelectron spectroscopy were used to document the change in the morphology and structure upon potential cycling of Pt/SiC catalysts. Two different potential cycle aging tests were used in order to accelerate the support corrosion, simulating start-up/shutdown and load cycling. On the basis of the results, we draw two main conclusions. First, platinized silicon carbide exhibits improved electrochemical stability over platinized active carbons. Second, silicon carbide undergoes at least mild oxidation if not even silicon leaching.

Keywords: accelerated stress test; electrochemical stability; electrochemical surface area; postmortem TEM; postmortem XPS; support corrosion.

Publication types

  • Research Support, Non-U.S. Gov't