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arXiv · 0906.2346

Using neutron spin-echo to investigate proton dynamics in proton-conducting perovskites

Maths Karlsson·Dennis Engberg·Mårten E. Björketun·Aleksandar Matic·Göran Wahnström·Per G. Sundell·Pedro Berastegui·Istaq Ahmed·Peter Falus·Bela Farago·Lars Börjesson·Sten Eriksson
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Abstract

We demonstrate the applicability of studying the proton dynamics in proton-conducting perovskites using neutron spin-echo spectroscopy, a powerful method hitherto neglected for studies of the proton dynamics in ceramic proton conductors. By combining our neutron spin-echo results of hydrated BaZr0.90Y0.10O2.95 with results obtained from kinetic modeling based on first-principles calculations we show that already over a length-scale as short as 2 nm the long-range proton self-diffusion is observed, and the likely effect of dopant atoms acting as trapping centers has averaged out.

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Maths Karlsson, Dennis Engberg, Mårten E. Björketun, Aleksandar Matic, Göran Wahnström, Per G. Sundell, Pedro Berastegui, Istaq Ahmed, Peter Falus, Bela Farago, Lars Börjesson, Sten Eriksson. 2009-06-12. Using neutron spin-echo to investigate proton dynamics in proton-conducting perovskites. https://arxiv.org/abs/0906.2346

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