posted on 2023-09-19, 02:30authored byAli Feizabadi, Jiatang Chen, Mohammad Norouzi Banis, Yun Mui Yiu, Lei Zhang, Xueliang Sun, Tsun-Kong Sham
Platinum (Pt) is a critical catalytic component used
in polymer
electrolyte membrane fuel cells. However, its low abundance, limited
supply, and increasing demand have limited the commercial applications
of this metal. One of the most recent ways to meet these demands is
to utilize Pt-based bimetallic nanoparticles. Using the Pt metal as
the shell material of the catalyst not only increases the surface
area but also creates an interfacial interaction between the core
metal and platinum, which results in enhanced catalytic activity.
Recently, octahedral Pd@Pt nanoparticles with controllable Pt shells
have been shown to exhibit greatly enhanced activity and durability
compared to commercial Pt/C. In this study, Pd@Pt nanoparticles will
be surface doped with cobalt to further boost their durability and
activity. Characterizing the synthesized catalyst with X-ray absorption
fine structure at the Pt L3-edge and cobalt K-edges, together with
performance tests, has revealed information about the effect of the
dopants on the catalytic activity of catalysts. The results of the
local and electronic structures of the catalysts are correlated with
electrocatalytic activity to optimize performance. Cobalt has been
found to be simultaneously efficient in enhancing catalytic activity,
increasing long-term durability, and reducing the platinum content
in the catalysts.