Surface engineered PdNFe3 intermetallic electrocatalyst for boosting oxygen reduction in alkaline media.

Surface engineering has been identified as an effective way to maximize the utilization of noble atoms and facilitate the oxygen reduction reaction. However, a cost-effective and highly durable platform for tailoring the electrocatalytic activity, is still absent. Herein, we demonstrate a new and promising catalytic material of antiperovskite-typed PdNFe 3 and construct a high performance PdNFe 3 @Pd catalyst with atomic layers of strained Pd shell. The PdNFe 3 @Pd/C catalyst presents a high mass activity (MA) of 1.14 A mg−1 Pd at 0.9 V, which is 9 and 6 times higher than those of the Pt/C and Pd/C, respectively. More importantly, the excellent performance of PdNFe 3 @Pd/C was also verified in anion-exchange membrane fuel cells and rechargeable Zn−air batteries. Density functional theory calculations reveal that the strain effect aroused by the lattice mismatch between PdNFe 3 core and Pd shell contributes to the enhanced ORR performance by optimizing the binding strength of oxygen intermediates on Pd. [Display omitted] • Demonstrating a new class of platform/core materials for constructing core-shell catalysts. • Elucidating catalytic mechanism of PdNFe 3 @Pd towards ORR. • Extraordinary catalytic performance towards oxygen reduction. [ABSTRACT FROM AUTHOR]