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Applying Dynamic Strain on Thin Oxide Films Immobilized on a Pseudoelastic Nickel-Titanium Alloy
Published on: July 28, 2020
Disentangling Electronic and Strain Effects in Core-Shell Pd@Pt Catalysts.
Qihao Li1, Zixiao Shi1, Michael Rebarchik2
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.
Journal of the American Chemical Society
|June 16, 2026
Summary
Researchers engineered palladium-platinum (Pd@Pt) core-shell nanocubes to boost electrocatalytic activity for hydrogen oxidation (HOR) and oxygen reduction (ORR). Electronic effects, not strain, significantly enhanced the platinum shell
Area of Science:
- Electrocatalysis
- Nanomaterials Science
- Surface Chemistry
Background:
- Enhancing intrinsic catalytic activity is crucial in electrocatalysis.
- Nanoscale core-shell structures can improve catalytic activity and atom utilization.
- Distinguishing strain effects from electronic interactions in core-shell catalysts is challenging.
Purpose of the Study:
- To develop a Pd@Pt core-shell nanocube system to isolate and investigate electronic effects on electrocatalytic activity.
- To quantify the catalytic enhancement for hydrogen oxidation (HOR) and oxygen reduction (ORR) reactions.
- To elucidate the dominant mechanism (strain vs. electronic effects) responsible for altered catalytic properties.
Main Methods:
- Synthesis of palladium-platinum (Pd@Pt) core-shell nanocubes.
- Electrochemical evaluation of HOR and ORR activity under alkaline conditions.
- X-ray photoelectron spectroscopy (XPS) for electronic structure analysis.
- Density functional theory (DFT) calculations to model strain and electronic effects.
Main Results:
- The Pd@Pt core-shell nanocubes showed over a 10-fold increase in catalytic activity for both HOR and ORR compared to pure platinum nanocubes.
- XPS analysis indicated a downshift in the Pt d-band center, suggesting altered electronic properties.
- DFT calculations confirmed that electronic effects, rather than lattice strain, were the primary contributors to the enhanced activity.
- Weakened binding of reaction intermediates due to electronic effects was identified as the key factor.
Conclusions:
- Electronic effects play a predominant role in enhancing the electrocatalytic activity of Pd@Pt core-shell nanocubes.
- The Pd@Pt system effectively minimizes strain effects, allowing for clear attribution of performance gains to electronic modulation.
- This study underscores the importance of understanding and controlling electronic interactions for designing high-performance electrocatalysts.
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