Stability of Pt-based Alloy Cathode Catalysts

In a recent review on the durability and degradation of PEM fuel cells, electrocatalyst stability was primarily ascribed to Pt dissolution under nonequilibrium conditions as well as Pt particle growth (sintering) during fuel cell operation [24], These issues also remain problematic for Pt-based alloy catalysts, whereas the stability of the alloying elements is an extra concern in alloy systems. The impact of alloying on the stability of cathode alloy catalysts in a PEM fuel cell environment can be considered from two perspectives negative effects and positive effects. 

Analysis of leaching causes has indicated that post-treatment of the alloy in acid media after preparation could mitigate the leaching effect on the stability of Pt 

With respect to the positive effects of Pt alloying, some improvement in catalyst stability and fuel cell durability have also been observed. Several studies [1, 27-29] have demonstrated that alloy particles have better resistance to sintering than pure platinum particles. The sintering effect may be attributed to base metals hindering Pt mobility on carbon, as well as Pt alloy particles usually being larger than Pt alone. Yu et al. [30] found that some platinum alloy catalysts, particularly 

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