Study of the Durability of Faceted Pt ₃Ni Oxygen-Reduction Electrocatalysts

The durability of truncated octahedral Pt ₃Ni (t,o-Pt ₃Ni) electrocatalysts in the oxygen-reduction reaction (ORR) was investigated by using an accelerated-durability-testing procedure. The Pt ₃Ni/C catalyst lost 21% of its initial electrochemical surface area (ECSA) and 40% of the mass-current density (0.55 to 0.33Amg _Pt ^-1) after 30000 potential cycles under acidic conditions. In comparison, the reference commercial Pt/C catalyst lost 44% of its initial ECSA and had a final mass-specific activity of only 0.09Amg _Pt ^-1 under identical testing conditions. This study shows the potentials of this class of Pt ₃Ni/C nanostructures as highly active and durable ORR catalysts.