Ion-Exchangeable, Electronically Conducting Layered Perovskite Oxyfluorides
- 23 June 2009
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 131 (28), 9849-9855
- https://doi.org/10.1021/ja9040829
Abstract
Cation-exchangeable d0 layered perovskites are amenable to intercalation, exfoliation, and a variety of topochemical reactions, but they lack the interesting electronic and magnetic functionalities of mixed-valent perovskites. Conversely, electronically and magnetically interesting layered perovskites lack scope in terms of interlayer chemistry. To bridge this gap, the insulating, cation-exchangeable layered perovskites RbLaNb2O7, KCa2Nb3O10, and NaYTiO4 were reacted with poly(tetrafluoroethylene) under inert atmosphere conditions to yield layer perovskites in which some of the oxygen is substituted by fluorine. In the fluorinated materials, the B-site cations are reduced to a mixed-valent state without introducing oxygen vacancies into the anion sublattice. The resulting electronically conducting solids can be exposed to air and water and even ion-exchanged in acid without oxidation of the B-site cations. Electronic transport measurements on the air-stable RbLaNb2O6F reveal room-temperature conductivity (2−7 × 102 Ω·cm) via a variable-range hopping mechanism, which is not substantially changed after aqueous proton exchange to H1−xRbxLaNb2O6F (x ≈ 0.2).This publication has 40 references indexed in Scilit:
- Review of the physics of high-temperature superconductorsPublished by Springer Science and Business Media LLC ,2008
- Preparation of a Blue Luminescent Nanosheet Derived from Layered Perovskite Bi2SrTa2O9Journal of the American Chemical Society, 2007
- Titanium Niobate and Titanium Tantalate Nanosheets as Strong Solid Acid CatalystsThe Journal of Physical Chemistry B, 2004
- Directly Rolling Nanosheets into NanotubesThe Journal of Physical Chemistry B, 2004
- Perovskites by Design: A Toolbox of Solid-State ReactionsChemistry of Materials, 2002
- Self-assembly of Tiled Perovskite Monolayer and Multilayer Thin FilmsChemistry of Materials, 2000
- Sr3Mn2O7: Mn4+Parent Compound of then=2 Layered CMR ManganitesJournal of Solid State Chemistry, 1998
- Unconventional magnetostriction in layered : Evidence for spin-lattice coupling abovePhysical Review B, 1997
- Luminescent Properties of Nondoped and Rare Earth Metal Ion-Doped K2La2Ti3O10 with Layered Perovskite Structures: Importance of the Hole Trap ProcessThe Journal of Physical Chemistry, 1995
- Possible highT c superconductivity in the Ba?La?Cu?O systemZeitschrift für Physik B Condensed Matter, 1986