title: Colossal ionic conductivity at interfaces of epitaxial ZrO2:Y2O3/SrTiO3 heterostructures.
abstract: The search for electrolyte materials with high oxygen conductivities is a key step toward reducing the operation temperature of fuel cells, which is currently above 700 degrees C. We report a high lateral ionic conductivity, showing up to eight orders of magnitude enhancement near room temperature, in yttria-stabilized zirconia (YSZ)/strontium titanate epitaxial heterostructures. The enhancement of the conductivity is observed, along with a YSZ layer thickness-independent conductance, showing that it is an interface process. We propose that the atomic reconstruction at the interface between highly dissimilar structures (such as fluorite and perovskite) provides both a large number of carriers and a high-mobility plane, yielding colossal values of the ionic conductivity.
authors.affiliation: Grupo de Física de Materiales Complejos, Universidad Complutense de Madrid, Madrid 28040, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Garcia-Barriocanal
authors.forename: A
authors.initials: A
authors.lastname: Rivera-Calzada
authors.forename: M
authors.initials: M
authors.lastname: Varela
authors.forename: Z
authors.initials: Z
authors.lastname: Sefrioui
authors.forename: E
authors.initials: E
authors.lastname: Iborra
authors.forename: C
authors.initials: C
authors.lastname: Leon
authors.forename: S J
authors.initials: SJ
authors.lastname: Pennycook
authors.forename: J
authors.initials: J
authors.lastname: Santamaria