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Among their numerous technological applications, semi-coherent oxide heterostructures have emerged as promising candidates for applications in intermediate temperature solid oxide fuel cell electrolytes, wherein interfaces influence ionic transport.Since misfit dislocations impact ionic transport in these materials, oxygen vacancy formation and migration at misfit dislocations in oxide heterostructures are central to their performance as an ionic conductor. Herein, we report high-throughput atomistic simulations to predict thousands of activation energy barriers for oxygen vacancy migration at misfit dislocations in SrTiO3/BaZrO3 heterostructures. Dopants display a noticeable effect as higher activation energies are uncovered in their vicinity. Interface layer chemistry has a fundamental influence on the magnitude of activation energy barriers since they are dissimilar at misfit dislocations as compared to coherent terraces. Lower activation energies are uncovered when oxygen vacancies migrate toward misfit dislocations, but higher energies when they hop away, revealing that oxygen vacancies would get trapped at misfit dislocations and impact ionic transport. The results herein offer atomic scale insights into ionic transport at misfit dislocations and fundamental factors governing the ionic conductivity of thin film oxide electrolytes.
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This content will become publicly available on March 1, 2027
Glassy Dynamics as a Predictive Framework for Lipid Exchange Across Membranes
ABSTRACT Lipid exchange between membranes is fundamental to biological function and technological applications, from drug delivery and vesicle trafficking to the design of biomimetic materials. Yet, quantitative prediction of both activation energies and timescales has remained elusive due to complex energy landscapes. Here, we present a thermodynamic–kinetic framework inspired by glassy dynamics to address this challenge. Using a single, experimentally accessible parameter—the thermal expansion coefficient of lipid vesicles—we apply the Collective Small Displacements (CSD) model to predict activation energies and transfer timescales without adjustable parameters. Our label‐free quartz crystal microbalance experiments validate these predictions across multiple lipid systems. We demonstrate that lipid exchange proceeds through rare, cooperative molecular events analogous to those governing relaxation in amorphous materials. By connecting a simple equilibrium thermodynamic property to interfacial transport dynamics, this work provides a versatile predictive tool for engineering lipid‐based materials and transport kinetics at the nanoscale, with broad implications for soft matter physics, synthetic biology, and nanobiotechnology.
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- PAR ID:
- 10685533
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Small
- Volume:
- 22
- Issue:
- 14
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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