title: Suppressed phase transition and giant ionic conductivity in La2Mo2O9 nanowires.
abstract: Improving the ionic conductivity of solid electrolytes at low temperatures represents a major challenge and an opportunity for enabling a variety of solid-state ionic devices for energy conversion and storage, as well as for environmental protection. Here we report a giant ionic conductivity of 0.20 Scm(-1), achieved at 500 °C, in the La2Mo2O9 nanowires with a bamboo-wire morphology, corresponding to a 1000-fold enhancement in conductivity over conventional bulk material. Stabilization of the high-temperature phase is observed to account for about a 10-fold increase in the conductivity. We further demonstrate that fast surface conduction in ∼3 nm thick, partially ordered, surface 'amorphous' films, under strain on the curved surfaces of the nanowires (as a non-autonomous surface phase or complexion), contributes to an enhancement of the conductivity by another two orders of magnitude. Exemplified here by the study of the La2Mo2O9 nanowires, new possibilities for improvement of conductivity and for miniaturization of solid-state ionic devices by the careful use of one-dimensional nanomaterials can be envisioned.
authors.affiliation: State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Pan
authors.affiliation: Department of NanoEngineering, Program of Materials Science and Engineering, University of California, San Diego, La Jolla, California 92093-0448, USA.
authors.forename: Jian
authors.initials: J
authors.lastname: Luo
authors.affiliation: State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Andy
authors.initials: A
authors.lastname: Godfrey
authors.affiliation: State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Ou
authors.affiliation: State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.affiliation: State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang