Activity enhancement of platinum oxygen-reduction electrocatalysts using ion-beam induced defects

High activity is one of the primary requirements for the catalysts in proton exchange membrane fuel cell applications. Platinum (Pt) is the best-known catalyst especially for oxygen reduction at the cathode; however, further activity improvements are still required. Previous computational studies suggested that the catalytic activity of Pt nanoparticles could be enhanced by a Pt−carbon support interaction. We have recently found that an enhanced electronic interaction occurs at the interface between an argon-ion (Ar⁺)-irradiated glassy carbon (GC) surface and Pt nanoparticles. Here, we report a more than two-fold increase in specific activity (SA) for the Pt nanoparticles on the Ar⁺-irradiated GC substrate compared to that on the non-irradiated GC substrate. The mechanism of this activity enhancement was investigated by local structure analysis of the interface. Ar⁺ irradiation of the carbon support led to the formation of the Pt−C bonding, thus protecting the deposited Pt nanoparticles from oxidation.