Unveiling the Mechanism of Exsolution of Silver Nanoparticles for Decorating Lanthanum Strontium Ferrite.

Lanthanum strontium ferrite (LaSrAgFeO = 0; LSFO) and its silver-doped derivative (LaSrAgFeO = 0.05; LASFO) are synthesized using mild conditions by a sol-gel method. Both oxides present a perovskite-like structure with orthorhombic symmetry due to octahedral tilting; thus, the incorporation of silver in the A-site does not significantly modify the perovskite structure.

Stability and Evolution of the Crystal Structure of TbBaCoO During Thermal Oxygen Release/Uptake.

A-site ordered double perovskites with the general formula LnBaCoO (where Ln is a lanthanide element) present electrical and electrocatalytic properties that make them attractive as possible ceramic electrode materials for solid oxide cells or alkaline electrolyzers. The properties are highly influenced by the anion vacancy concentration, which is strongly related to the Co-oxidation state, and their location in the structure. Awareness of the stable phases is essential to synthesize, evaluate, and optimize the properties of LnBaCoO oxides at operating conditions in different applications.

Superior Performance as Cathode Material for Intermediate-Temperature Solid Oxide Fuel Cells of the Ruddlesden-Popper = 2 Member EuSrCoFeO with Low Cobalt Content.

The effects of the contents of iron and cobalt on the crystal structure, oxygen content, thermal expansion coefficient, and electrical-electrochemical properties of materials EuSrCoFeO ( = 0.50 and 1.00) are reported.

The Effects of Sr Content on the Performance of NdSrCoO Air-Electrode Materials for Intermediate Temperature Solid Oxide Fuel Cells under Operational Conditions.

The potential of the perovskite system NdSrCoO ( = 1/3 and 2/3) as cathode material for solid oxide fuel cells (SOFCs) has been investigated via detailed structural, electrical, and electrochemical characterization. The average structure of = 1/3 is orthorhombic with a complex microstructure consisting of intergrown, adjacent, perpendicularly oriented domains. This orthorhombic symmetry remains throughout the temperature range 373-1073 K, as observed by neutron powder diffraction.

Novel Perovskite Materials for Thermal Water Splitting at Moderate Temperature.

Materials with the formula Sr CoNb Ti O (x=1.00, 0.70; δ=number of oxygen vacancies) present a cubic perovskite-like structure.

Defect Chemistry, Electrical Properties, and Evaluation of New Oxides Sr CoNb Ti O (0≤x≤1) as Cathode Materials for Solid Oxide Fuel Cells.

The perovskite series Sr CoNb Ti O (0≤x≤1) was investigated in the full compositional range to assess its potential as cathode material for solid oxide fuel cell (SOFC). The variation of transport properties and thus, the area specific resistances (ASR) are explained by a detailed investigation of the defect chemistry. Increasing the titanium content from x=0-1 produces both oxidation of Co to Co (from 0 up to 40 %) and oxygen vacancies (from 6.

Synthesis and characterization of NaNiF3·3H2O: an unusual ordered variant of the ReO3 type.

A new hydrated sodium nickel fluoride with nominal composition NaNiF3·3H2O was synthesized using an aqueous solution route. Its structure was solved by means of ab initio methods from powder X-ray diffraction and neutron diffraction data. NaNiF3·3H2O crystallizes in the cubic crystal system, space group Pn3̅ with a = 7.

Complex magnetic behaviour of Sr2CoNb1-xTixO6 (0 ≤ x ≤ 0.5) as a result of a flexible microstructure.

We report the rich magnetic behaviour of Sr2CoNb1-xTixO6 (0 ≤ x ≤ 0.5) oxides as a result of their complex microstructure. Although these oxides show an average simple-cubic perovskite structure, they present a flexible microstructure due to short-range ordering between Co/Ti and Nb cations in the perovskite B-sites.

New perovskite materials of the La(2-x)Sr(x)CoTiO6 series.

Substitution of La(3+) by Sr(2+) in the double perovskite La(2)CoTiO(6) yields materials of the La(2-x)Sr(x)CoTiO(6) series showing a significant amount of trivalent cobalt ions when prepared at ambient atmosphere. The as-prepared compounds can be reduced in severe conditions retaining the perovskite structure while inducing the formation of a large amount of oxygen vacancies. The limit of aliovalent substitution in this series was found to extend up to x = 1.

Insight into ramsdellite LI(2)Ti(3)O(7) and its proton-exchange derivative.

Despite being proven to be a good lithium-ion conductor 30 years ago, the crystal structure of the ramsdellite-like Li(2)Ti(3)O(7) has remained uncertain, with two potential models for locating the lithium ions in the structure. Although the model presently accepted states that both lithium and titanium occupy the octahedral sites in the framework, evidence against this model are provided by (6)Li and (7)Li MAS NMR spectroscopy. Thus, about 14% of these octahedral positions are empty since no lithium in octahedral coordination is present in the material.

Supramolecular architecture and magnetic properties of copper(II) and nickel(II) porphyrinogen-TCNQ electron-transfer salts.

The compounds [Cu(Tz)-(MeOH)2](TCNQ)2 (1), [Ni(Tz)-(MeOH)2](TCNQ)2 (2), [Cu(Tz)2]-(TCNQ)7 (3) and [Ni(Tz)2](TCNQ)7 (4) (Tz = 2,7,12,17-tetramethyl-1,6,11,16-tetraazaporphyrinogen) were obtained by metathesis reaction of [M(Tz)](ClO4)2 with LiTCNQ and Et3NH(TCNQ)2, respectively. They were characterized by a combination of spectroscopic and physical methods. Compound 1 crystallizes in the monoclinic space group P2(1)/n with a = 8.

Magnetic Behavior and Crystal Structure of [Fe(cyclam)(NCS)(2)](TCNQ)(2): An Unusual One-Dimensional (TCNQ)(2)(-) Radical-Ion System.

The compound [Fe(cyclam)(NCS)(2)](TCNQ)(2), where cyclam is 1,4,8,11-tetraazacyclotetradecane and TCNQ is a partially reduced 7,7,8,8-tetracyanoquinodimethane fragment, has been obtained from the corresponding thiocyanate by metathesis reaction. The compound crystallizes in the triclinic system, space group P&onemacr;, a = 7.832(3) Å, b = 8.