1 research outputs found
Ultrathin Icosahedral Pt-Enriched Nanocage with Excellent Oxygen Reduction Reaction Activity
Cost-efficient utilization
of Pt in the oxygen reduction reaction
(ORR) is of great importance for the potential industrial scale demand
of proton-exchange membrane fuel cells. Designing a hollow structure
of a Pt catalyst offers a great opportunity to enhance the electrocatalytic
performance and maximize the use of precious Pt. Herein we report
a routine to synthesize ultrathin icosahedral Pt-enriched nanocages.
In detail, the Pt atoms were conformally deposited on the surface
of Pd icosahedral seeds, followed by selective removal of the Pd core
by a concentrated HNO<sub>3</sub> solution. The icosahedral Pt-enriched
nanocage that is a few atomic layers thick includes the merits of
abundant twin defects, an ultrahigh surface/volume ratio, and an ORR-favored
Pt{111} facet, all of which have been demonstrated to be promoting
factors for ORR. With a 10 times higher specific activity and 7 times
higher mass activity, this catalyst shows more extraordinary ORR activity
than the commercial Pt/C. The ORR activity of icosahedral Pt-enriched
nanocages outperforms the cubic and octahedral nanocages reported
in the literature, demonstrating the superiority of the icosahedral
nanocage structure