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DOE OSTI · 2540204

Iridium Nanocrystals Enriched with Defects and Atomic Steps to Enhance Oxygen Evolution Reaction Performance

Ikram, Farhat [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000164010759)·Cheong, Soshan [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000161330829)·Persson, Ingemar [Linköping University (Sweden)] (ORCID:0000000226764856)·Ramadhan, Zeno R. [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000170428780)·Poerwoprajitno, Agus Riyanto [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies] (ORCID:0000000219328669)·Gooding, J. Justin [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000253980597)·Tilley, Richard D. [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:000000032097063X)
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Abstract

The presence of defects can significantly improve catalytic activity and stability, as they influence the binding of the reactants, intermediates, and products to the catalyst. Controlling defects in the structures of nanocrystal catalysts is synthetically challenging. In this study, we demonstrate the ability to control the growth of Ir nanocrystals, enabling the tuning of both structural and surface defects. The Ir nanocrystals have unique structures that range from single crystals of a few nanometers to twinned nanoparticles and multiply twinned crystallites with a high density of atomic steps. Further, this approach of defect engineering enables us to understand their roles in enhancing the performance of the OER and producing an Ir catalyst with both high activity and stability. Our results show the importance of the concept of using synthetic control of structural and surface defects in metal nanoparticles as a strategy to improve catalytic performance.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYCatalystsCrystal structureDefectsNanoparticlesTransition metals

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Ikram, Farhat [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000164010759), Cheong, Soshan [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000161330829), Persson, Ingemar [Linköping University (Sweden)] (ORCID:0000000226764856), Ramadhan, Zeno R. [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000170428780), Poerwoprajitno, Agus Riyanto [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies] (ORCID:0000000219328669), Gooding, J. Justin [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:0000000253980597), Tilley, Richard D. [Univ. of New South Wales, Sydney, NSW (Australia)] (ORCID:000000032097063X). 2025-03-12. Iridium Nanocrystals Enriched with Defects and Atomic Steps to Enhance Oxygen Evolution Reaction Performance. https://doi.org/10.1021/jacs.5c02151

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