The critical region determining the performance and lifetime of solid oxide electrochemical systems is normally at the electrode side of the electrode/electrolyte interface. Typically this electrochemically active region only extends a few micrometres and for best performance involves intricate structures and nanocomposites. Much of the most exciting recent research involves understanding processes occurring at this interface and in developing new means of controlling the structure at this interface on the nanoscale. Here we consider in detail the diverse range of materials architectures that may be involved, describe the evolution of these interface structures and finally explore the new chemistries that allow control and manipulation of these architectures to optimize both performance and durability.
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C.C. acknowledges financial support from ECoProbe (DFF – 4005-00129) funded by the Danish Independent Research Council. C.G. and M.B.M. acknowledge financial support from Energinet.dk through the ForskEL programme Solid Oxide Fuel Cells for the Renewable Energy Transition contract no. 2014-1-12231. J.T.S.I., M.C.V. and D.N. acknowledge support from EPSRC Platform Grant EP/K015540/1, EPSRC Tailoring of microstructural evolution in impregnated SOFC electrodes EP/M014304/1 and Royal Society Wolfson Merit Award WRMA 2012/R2.
The authors declare no competing financial interests.
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Irvine, J., Neagu, D., Verbraeken, M. et al. Evolution of the electrochemical interface in high-temperature fuel cells and electrolysers. Nat Energy 1, 15014 (2016). https://doi.org/10.1038/nenergy.2015.14
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