Answers are grounded in this paper and cite their sources.
Surface segregation of the non-noble component of a Pt bimetallic core-shell catalyst can occur even at room temperature under typical fuel cell cathode application conditions. While in an alkaline environment the nanoparticles remain stable, and the alteration in the surface composition can be tracked in situ; in an acidic electrolyte, any non-noble alloying material at the surface would immediately dissolve into the electrolyte. Therefore, such catalysts are expected to degrade steadily during operation in an acidic fuel cell until only Pt is left.
No takes yet. Share an insight, caveat, or question.
Mayrhofer et al. (2009) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: