(525e) Highly Active and Durable Pt-Bimetallic Electrocatalysts

Wang, C., Argonne National Laboratory
Markovic, N., Argonne National Laboratory

Development of advanced nanomaterials relies on the tuning of material structure at nanoscale.  This is in particular manifested in the design of electrocatalysts demanding both high catalytic activity and durability.  Here we report the nanoscale architecture of a Pt-bimetallic catalyst with Pt enriched near-surface layers, which shows superior electrocatalytic performance for the oxygen reduction reaction (ORR).  The desirable architecture was first established on extended surfaces with customized composition profiles and then realized in nanocatalysts via organic solution synthesis.  Electrochemical studies for the ORR demonstrated that the novel Pt-bimetallic catalyst exhibited improvement factors in mass activity of more than six times before, and over one order of magnitude after elongated potential cycling versus conventional Pt catalysts.