Climbing the oxygen reduction reaction volcano plot with laser ablation synthesis of PtxY nanoalloys

Abstract

According to Nørskov d-band theory, the Pt_xY alloy was predicted to be among the most active catalysts for the oxygen reduction reaction (ORR). To achieve the high surface area needed in proton exchange membrane fuel cells, this alloy must be synthesized as a nanophase in a scalable fashion. However, the synthesis of Pt_xY nanoparticles cannot be accomplished with the common chemical methods due to the high oxophilicity of yttrium. Here we present the successful preparation of Pt_xY nanoparticles in one step by laser ablation in liquid of a Pt₃Y target. The formation of Pt_xY nanoparticles was confirmed by TEM, XRD and XPS analyses. The ORR activity was evaluated in 0.1 M HClO₄ revealing superior mass activity (483 A g⁻¹) and specific activity (0.562 mA cm⁻²) to a Pt/C TKK standard.