Pt monolayer (ML) electrocatalysts offer a dramatically reduced Pt content while providing considerable possibilities for enhancing their catalytic activity and stability for the oxygen reduction reaction (ORR) at fuel cell (FC) cathodes. The achievements in highly active, stable Pt ML on Pd-based nanoparticle catalysts for the ORR have been described elsewhere^1-3. Various spectroscopic and microscopic studies coupled with theoretical calculations have revealed that their high advantageous characteristics resulted from the geometric and electronic interactions between the cores and the Pt MLs, together with the self-healing effect induced by the supporting cores. In order to further improve the electrochemical performance and reduce total costs toward commercialization, the composition, shape, and size of cores need to be optimized. Recently we have developed several novel nanostructured cores, such as Ir-based core-shell and alloy cores⁴, nitride-stabilized core components^5-7, and structurally ordered intermetallic cores⁸to enhance the properties of the Pt ML shells. In the present paper, we will focus on the results of newly-developed nitride cores for the Pt ML electrocatalysts and discuss potentials of the approach. We believe that the results from the Pt ML electrocatalysts significantly impact the research of electrocatalysis and FC technology, as they demonstrate an exceptionally effective way of using Pt that can resolve problems encountered in other approaches.

Acknowledgements:

This manuscript has been authored by employees/guest of Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy. The publisher by accepting the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes.

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