Facile synthesis of Pd3Y alloy nanoparticles for electrocatalysis of the oxygen reduction reaction

Multielement nanocrystals made of noble metals and transition metals are at the focus of theoretical and experimental studies for their promising performances in several key electrochemical processes of the renewable energies landscape. However, the preparation of bimetallic nanocrystals often requires expensive and tedious procedures, sometimes resulting in nanocrystals contaminated at their surface by synthesis byproducts. In this paper we describe the synthesis of Pd3Y alloy nanoparticles (NPs) by a robust laser assisted method in pure organic solvents and their performances as electrocatalysts for oxygen reduction reaction (ORR). The electrochemical properties of Pd3Y NPs for ORR, investigated in acid and alkaline electrolytes, exhibited higher activity than standard Pd/C or Pt/C systems, in terms of half wave potential, mass activity and specific activity, in agreement with the predictions of the Norskov d-band center model for Pd alloys. The effect of ClO4- and Cl- anions was also investigated revealing a surprising poisoning effect of both anions for the Pd3Y alloys. Overall, laser generated Pd3Y alloy NPs emerged as highly active nanosystems for ORR, opening the way to the realization of other nanoalloys of potential interest in the perspective of Pt replacement by the same synthetic route. (C) 2019 Elsevier Ltd. All rights reserved.