© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Nanoionics has become an increasingly promising field for the future development of advanced energy conversion and storage devices, such as batteries, fuel cells, and supercapacitors. Particularly, nanostructured materials offer unique properties or combinations of properties as electrodes and electrolytes in a range of energy devices. However, the enhancement of the mass transport properties at the nanoscale has often been found to be difficult to implement in nanostructures. Here, an artificial mixed ionic electronic conducting oxide is fabricated by grain boundary (GB) engineering thin films of La0.8Sr0.2MnO3+δ. This electronic conductor is converted into a good mixed ionic electronic conductor by synthesizing a nanostructure with high density of vertically aligned GBs with high concentration of strain-induced defects. Since this type of GBs present a remarkable enhancement of their oxide-ion mass transport properties (of up to six orders of magnitude at 773 K), it is possible to tailor the electrical nature of the whole material by nanoengineering, especially at low temperatures. The presented results lead to fundamental insights into oxygen diffusion along GBs and to the application of these engineered nanomaterials in new advanced solid state ionics devices such are micro-solid oxide fuel cells or resistive switching memories. An electronic conductor such as La0.8Sr0.2MnO3+δ is converted into a good mixed ionic electronic conductor by synthesizing a nanostructure with excellent electronic and oxygen mass transport properties. Oxygen diffusion highways are created by promoting a high concentration of strain-induced defects in the grain boundary region. This novel strategy opens the way for synthesizing new families of artificial mixed ionic-electronic conductors by design.
|Original language||English (US)|
|Journal||Advanced Energy Materials|
|State||Published - Apr 9 2015|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: A.M.S. and D.P. contributed equally to this work. The research was supported by the Ministerio de Economia y Competitividad (ENE2013-47826), Generalitat de Catalunya-AGAUR (2014 SGR 1638), and the European Regional Development Funds (ERDF, "FEDER Programa Competitivitat de Catalunya 2007-2013"). A.T., A.M., and M.B. would like to thank for the financial support of the Ramon y Cajal and Juan de la Cierva postdoctoral programs, respectively. A.C. acknowledges the financial support of Kaust.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.