Favorable Core/Shell Interface within Co2P/Pt Nanorods for Oxygen Reduction Electrocatalysis

Chang Liu; Zhong Ma; Meiyang Cui; Zhiyong Zhang; Xu Zhang; Dong Su; Christopher B Murray; Jia X Wang; Sen Zhang

doi:10.1021/acs.nanolett.8b03666

Favorable Core/Shell Interface within Co₂P/Pt Nanorods for Oxygen Reduction Electrocatalysis

Nano Lett. 2018 Dec 12;18(12):7870-7875. doi: 10.1021/acs.nanolett.8b03666. Epub 2018 Nov 19.

Authors

Chang Liu¹, Zhong Ma², Meiyang Cui¹, Zhiyong Zhang¹, Xu Zhang³, Dong Su⁴, Christopher B Murray⁵, Jia X Wang², Sen Zhang¹

Affiliations

¹ Department of Chemistry , University of Virginia , Charlottesville , Virginia 22904 , United States.
² Chemistry Division, Energy and Photon Sciences Directorate , Brookhaven National Laboratory , Upton , New York 11973 , United States.
³ Department of Physics and Astronomy , California State University Northridge , Northridge , California 91330 , United States.
⁴ Center for Functional Nanomaterials , Brookhaven National Laboratory , Upton , New York 11973 , United States.
⁵ Department of Chemistry , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States.

PMID: 30427689
DOI: 10.1021/acs.nanolett.8b03666

Abstract

Nanostructures with nonprecious metal cores and Pt ultrathin shells are recognized as promising catalysts for oxygen reduction reaction (ORR) to enhance Pt efficiency through core/shell interfacial strain and ligand effects. However, core/shell interaction within a real catalyst is complex and due to the presence of various interfaces in all three dimensions is often oversimply interpreted. Using Co₂P/Pt core/shell structure as a model catalyst, we demonstrate, through density functional theory (DFT) calculations that forming Co₂P(001)/Pt(111) interface can greatly improve Pt energetics for ORR, while Co₂P(010)/Pt(111) is highly detrimental to ORR catalysis. We develop a seed-mediated approach to core/shell Co₂P/Pt nanorods (NRs) within which Co₂P(001)/Pt(111) interface is selectively expressed over the side facets and the undesired Co₂P(010)/Pt(111) interface is minimized. The resultant Co₂P/Pt NRs are highly efficient in catalyzing ORR in acid, superior to benchmark CoPt alloy and Pt nanoparticle catalyst. As the first example of one-dimensional (1D) core/shell nanostructure with an ultrathin Pt shell and a nonprecious element core, this strategy could be generalized to develop ultralow-loading precious-metal catalysts with favorable core/shell interactions for ORR and beyond.

Keywords: Core/shell; interface; nanorod; oxygen reduction; seed-mediated synthesis.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.