Microscopic model of intergrain boundary junction

The statistical mechanics differential-difference equations for the ions concentration distribution that account for the diffusion, electrical conductivity and Poisson contributions are derived. They represent differential-difference analogues of the phenomenological continuity equations for the ions. Spatial inhomogeneities (grain interiors, grain boundaries, intergrain regions, etc.) can easily be taken into account by proper adjusting the system material parameters (diffusion coefficients or particle transition rates, electric conductivities, thermodynamic factors or chemical capacitances). The solution of the equations allows investigating impedance spectra of inhomogeneous systems, e. g. electro-conducting ceramics. The results can be used for interpretation of experimental impedance spectra and evaluation of the medium transport characteristics. A simple example of the intergrain boundary junction is considered

NMR Investigations in Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 Ceramics. Part I: Structural Aspect

International audienc

Lithium Ion Conductors in the System Li4xTi1-xP2O7 ( x= 0; 0,06; 0,2)

The powder of Li4xTi1-xP2O7 (x = 0.06, 0.1, 0.2) pyrophosphates - potentially suitable electrode materials for lithium secondary batteries - have been synthesized by solid state reaction. The analysis of the XRD patterns showed that these pyrophosphates have cubic 3x3x3 superstructure (S.G. Pa ) with 108 formula units in the supercell. The complex electrical conductivity were carried out in air from 400 K to 720 K and in the frequency range from 10 Hz to 3 GHz. Two relaxation dispersion regions in conductivity spectra were foun

Formation and characteristics of thin films of ZrO2-8 mol % Y2O3 solid electrolytes

[6th International Conference on Self-Formation Theory and Applications Vilnius, Lithuania, Nov. 26-28, 2003]Thin films of ZrO2-8mol % Y2O3 have been deposed by pulsed DC magnetron sputtering method. The substrates of Ni-cermet and alloy-600 for the films were used. The results of the investigation of the X-ray diffraction patterns and SEM showed that the films are nanocrystalline and belong to cubic symmetry. The relaxation process is related to the ion transport in thin films. The results of the investigation of the temperature dependencies of thin films ionic conductivity showed that the dependence (T) is caused by the temperature dependence of oxygen vacancy mobility, while the number of charge carriers remains constant with temperatureLietuvos energetikos institutas, [email protected] universitetasVilniaus universitetas, [email protected] universitetas, [email protected] Didžiojo universiteta

Zr2-8 mol.% Y2O3 plonųjų sluoksnių gamybos technologija ir jų elektrinės savybės

Pateiktos ZrO2-8 mol.% Y2O3 plonųjų sluoksnių gamybos technologinės sąlygos, naudojant impulsinį magnetroną, o taip pat aprašyti sluoksnių joninio laidumo sando temperatūriniai ir dažniniai tyrimai. Elektriniai matavimai atlikti 300-1000 K temperatūrų intervale ir 2 10(4)-10(6) Hz dažnių diapazone. Plonųjų sluoksnių nusodinimas vyko 0,25-1,8 Pa slėgio O2 dujose. Sluoksniai buvo formuojami ant lydinio 600 bei 5 sv.% CSY/95 sv.% NiO padėklų. Kintamajame 2 10(4)-10(6) Hz dažnių elektriniame lauke aptikta relaksacinė elektrinių parametrų dispersija, kuri siejama su VO-- pernaša plonuosiuose sluoksniuose. Parodyta, kad temperatūrinį kristalitinio laidžio kitimą daugiausia lemia VO- krūvininkų judrio temperatūrinis kitimasThin films of ZrO2-8 mol.% Y2O3 have been deposed by pulsed magnetron sputtering on Ni-cermet and alloy-600 substrates. Investigation of the X-ray diffraction patterns and SEM has shown that the films are polycrystalline and belong to cubic symmetry. The relaxation process is related to the ion transport in thin films. Investigation of the temperature dependences of thin film ionic conductivity [sigma] has shown that the dependence [sigma](T) is caused by the temperature dependence of oxygen vacancy mobilityLietuvos energetikos institutas, [email protected] universitetasVytauto Didžiojo universiteta