Effect of Core Size on Activity and Durability of Pt Core-Shell Catalysts for PEFCs

Abstract

Pt/Au/C and Pt/Pd/C core-shell catalysts were prepared from Au/C and Pd/C cores with different core sizes using under potential deposition (UPD) of Cu, and the activity for oxygen reduction reaction and durability of the Pt/Au/C and Pt/Pd/C catalysts were investigated. Pt/Au/C and Pt/Pd/C core-shell catalysts showed higher mass activities than a commercially available Pt2.8nm/C catalyst, and hence they are promising for reducing the Pt usage in PEFCS. In potential cycling durability tests between 0.6-1.0 V, opposite effects of core size on were observed for Pt/Au/C and Pt/Pd/C. For Pt/Au/C, smaller cores gave high durability, whereas for Pt/Pd/C, larger cores gave high durability comparable with the Pt2.8nm/C.