Entropy-driven oxygen transport anisotropy and spin-state manipulation for high-performance reversible solid oxide cells
File(s)
Supporting information
Accepted version
Author(s)
Type
Journal Article
Abstract
Reversible solid oxide cells (SOCs) play a pivotal role in sustainable energy storage and carbon neutrality, where the efficiency is limited by the intrinsic oxygen surface exchange and bulk transport of air electrodes—two interconnected yet often competing processes. Here, we report an entropy-driven effect to simultaneously optimize both kinetics. After introducing A-site configurational entropy to form La0.2Nd0.2Pr0.2Ca0.2Sr0.2CoO3 (LSC-PrCa) while meticulously preserving the divalent doping concentration and average ionic radius, significant local lattice distortion was successfully induced with A-O bonding gradient and site-selective oxygen vacancy distribution. Combined neutron scattering, in situ synchrotron spectroscopy, and theoretical calculations reveal that this entropy-induced distortion generates unusual anisotropic oxygen diffusion pathways in simple perovskite structure, resulting in substantially enhanced bulk transport. Furthermore, it stabilizes high-spin Co3+ states at operating temperatures, which accelerates surface catalysis beyond the classical O 2p-band mechanism. Consequently, LSC-PrCa electrode delivers a 10-fold increase in both oxygen bulk diffusivity and surface exchange coefficients, achieving up to 56% improvement in reversible fuel and electrolysis cell performance with good short-term stability. Notably, this ranks among the highest for zirconia electrolyte-supported cells. This work discloses new mechanisms in entropy engineering to decouple surface and bulk kinetics, providing a general design paradigm for high-performance electrochemical materials.
Date Issued
2027-03-01
Date Acceptance
2026-08-18
Citation
Applied Catalysis B: Environment and Energy, 2027, 402
ISSN
0926-3373
Publisher
Elsevier BV
Start Page
127433
End Page
127433
Journal / Book Title
Applied Catalysis B: Environment and Energy
Volume
402
Copyright Statement
Copyright © 026 Elsevier B.V. This is the author’s accepted manuscript made available under a CC-BY licence in accordance with Imperial’s Research Publications Open Access policy (www.imperial.ac.uk/oa-policy)
License URL
Publication Status
Published
Article Number
127433
Date Publish Online
2026-08-31