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Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles.

ABSTRACT: Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surface layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. Our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments.

SUBMITTER: Ulvestad A

PROVIDER: S-EPMC4682038 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles.

Ulvestad A A Welland M J MJ Collins S S E SS Harder R R Maxey E E Wingert J J Singer A A Hy S S Mulvaney P P Zapol P P Shpyrko O G OG

Nature communications 20151211

Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformat ...[more]

PMID: 26655832

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Dataset Information

Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles.

Publications

Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles.

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