The purpose of this chapter is to understand the ionic conduction of perovskite-type oxides. It is based on the fundamental theories of perovskite structure, ionic conductivity, conductivity measurement, X-ray diffraction and Rietveld analysis, and nuclear magnetic resonance (NMR). Typical examples of lithium ionic conductor are introduced. Introduction Perovskite-type oxides have been consider...

•Large entropy of reduction and intermediate enthalpy reduction•pO2-dependent reversible structural transition: orthorhombic ? tetragonal cubic•Outstanding H2 yield 10 mL g?1 upon at 1,350°C a cycle time 1.5 h•H2 production rate limited by gas-phase mass transport rather than material kinetics A global transition away from fossil fuel energy to sustainable sources, in particular solar energy, r...

We report here the results of vacuum tunneling spectroscopy of rare-earth manganates which show colossal magnetoresistance (CMR) and charge ordering (CO). Three samples with different hole concentrations and average A site cation radii have been studied. A charge-ordering gap (∆CO) opens up in the density of states (DOS) near EF, below the charge-ordering transition. A gap comparable to the tra...

We generate a series of Zr pseudopotentials and use them to calculate the properties of PbZrOs, in order to examine the relationship between pseudo-atomic properties and solid-state oxide results. We find that lattice constants and bond lengths within the oxide unit cell are quite sensitive to pseudopotential construction errors, and clear correlations emerge. These trends motivate our identifi...

Scanning micro-Raman spectroscopy has been utilized to image and investigate strain in He-implanted congruent LiNbO3 samples. By using abruptly patterned implanted samples, we show that the spatial twodimensional mapping of the Raman spectral peaks can be used to image the strain distribution and determine its absolute magnitude. We demonstrate that both shortand long-range length-scale in-plan...

In analogy to the role of oxide anion in perovskites, halogen chemistry halide perovskites significantly contributes chemical, physical, and optoelectronic properties this class materials.Investigating manipulating site has improved our understanding electronic structure, reactivity, defect chemistry, ionic conductivity perovskites.A clear is expected (i) yield novel with targeted controlled (i...

Using DFT methods we have studied structure, equation of state, and phase behavior of BaTiO3. We have identified the pressure induced phase transformations from the rhombohedral to orthorhombic structure at ca. 5 GPa and from tetragonal phase to cubic phase at ca. 7.5 GPa. INTRODUCTION BaTiO3 is an important example perovskite structured ceramic displaying ferroelectric property. At high temper...

Bulk samples of La2.3-xYxCa0.7Mn2O7, x=0,0.3,0.5, with layered perovskite structure have been synthesized and investigated with respect to their electrical, electronic and magnetic properties. It is found that La1.8Y0.5Ca0.7Mn2O7 has tetragonal structure and is a metallic ferromagnet with a magnetic transition temperature of 170 K. The compound shows metallic behavior below 140 K and has a larg...