Revealing Dynamic Structural Changes in Platinum-Group-Metal Nanoparticles during the Catalytic Hydrogen Evolution
Yuto Maruta1, Hirotaka Ashitani2, Shogo Kawaguchi2
1Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Journal of the American Chemical Society
|October 1, 2025
Summary
Smaller platinum-group metal nanoparticles show significant structural changes during the hydrogen evolution reaction (HER). Their size and composition crucially impact dynamics, influencing catalyst design for improved electrochemical performance.
Area of Science:
- Materials Science
- Electrochemistry
- Nanotechnology
Background:
- Structural dynamics of nanoparticles (NPs) are vital for catalytic reactions.
- The impact of NP size and composition on electrochemical dynamics is understudied.
Purpose of the Study:
- To systematically investigate the size- and element-dependent structural and electronic dynamics of platinum-group-metal (PGM) NPs.
- To understand these dynamics during the hydrogen evolution reaction (HER) under acidic and alkaline conditions.
Main Methods:
- Operando powder X-ray diffraction (XRD).
- Operando X-ray absorption spectroscopy (XAS).
Main Results:
- Smaller NPs exhibited more significant structural changes, linked to surface adsorbate-induced dynamics.
- Platinum (Pt), Palladium (Pd), and Rhodium (Rh) NPs showed slow lattice expansion (tens of seconds) and reductive electronic states.
- Ruthenium (Ru) NPs remained oxidized during HER, unlike other PGMs.
Conclusions:
- NP size and composition significantly influence structural and electronic changes during electrochemical reactions.
- Findings provide a framework for operando catalyst studies and designing optimized HER catalysts.
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