Enhanced ionic motion in some fluorite-structured solid solutions
نویسنده
چکیده
Bulk ionic conductivity, Ionic Thermal Current (I.T.C.), and Thermally Stimulated Polarization Current (T.S.P.C.) studies are reported for the system Bal-,LaXF2+, (0.12 x loe2 < x < 0.45). The obtained results are illustrative for the compositional dependence of the ionic conductivity of anion-excess solid solutions. For small solute content simple associates as well as free mobile fluoride interstitials are present. For x > 0.01 defect clusters form. The ionic conductivity in this concentration range is characterized by Enhanced Ionic Motion.
منابع مشابه
Oxygen Ion and Mixed Conductivity in Compounds with the Fluorite and Pyrochlore Structure
The effect of pyrochlore order in solid solutions with the defect fluorite structure was studied. The amount of order was changed by various heat treatments or by varying the cation composition. Examples of short range order and microdomainformation have been observed in Tb2Zr207+x and Gd2Zr207. Pyrochlore order results in a decrease of the activation enthalpy and pre-exponential factor for oxy...
متن کاملStructural and Mechanistic Insights into Fast Lithium-Ion Conduction in Li4SiO4-Li3PO4 Solid Electrolytes.
Solid electrolytes that are chemically stable and have a high ionic conductivity would dramatically enhance the safety and operating lifespan of rechargeable lithium batteries. Here, we apply a multi-technique approach to the Li-ion conducting system (1-z)Li4SiO4-(z)Li3PO4 with the aim of developing a solid electrolyte with enhanced ionic conductivity. Previously unidentified superstructure and...
متن کاملInterface Analysis of Complex Oxide Ceramics in Electrolyte Supported Solid Oxide Fuel Cell
Solid Oxide Fuel Cells (SOFC) offer electrochemically generated sources of electricity using oxygen ion transport at elevated temperatures. Analysis of materials used in SOFC using electron microscopy provides insights of foreseeable chemical reactions that govern the performance of the fuel cell. Materials used in SOFC can be divided into four categories; anode, cathode, electrolyte and interc...
متن کاملStructure and Conductivity of Pyrochlore and Fluorite Type Solid Solutions
High oxygen conductivities can be achieved in cation ordered LnxZrl_=O2_l x (Ln=Gd, Nd) solid solutions with pyrochlore (P) structure. High values of the pre-exponentlal factor °o are correlated with the degree of anion disorder in the 8b oxygen sublattice (neutron diffraction). The activation energy AH is lowered by cation ordering (F-P transition; effect of x) due to the occurence of a prefer...
متن کاملOptimizing ionic conductivity in doped ceria
David Andersson et al. report calculations revealing how doped oxides with cubic fluorite structures become effective ionic conductors. Cubic fluorite structures, such as ceria (CeO2), can become effective ionic conductors when doped with cations of lesser valence than the host cations. Doped ceria thus has potential as an electrolyte for environmentally friendly solid oxide fuel cells. Anderss...
متن کامل