52 Result(s)

Article

Effects of some technological factors on the properties of current-carrying films

G. G. Mamedova, S. P. Rodtsevich, V. V. Kharton, E. N. Naumovich in Glass and Ceramics (1993)

Article

Ionic and electronic transport in perovskite-type La(Ga,M)O_3−δ (M=Mg, Cr, Fe, Co, Ni, Nb)

Oxygen ion conduction in La_0.9Sr_0.1Ga_1−xM_xO_3−δ (M=Cr, Fe; x=0 – 0.20), LaGa_1−xM_xO_3−δ (M=Co, Ni; x=0.20 – 0.60), LaGa_1−x−yCo_xMg_yO_3−δ (x=0.35 – 0.60; y=0.10 – 0.25) and LaGa_0.85−xMg_0.15(Nb_0.33Mg_0.66)_xO_3−δ (x=0 – 0....

V. V. Kharton, E. N. Naumovich, F. M. B. Marques in Ionics (1999)

Article

Physicochemical and Transport Properties of Bicuvox-Based Ceramics

Polycrystalline Bi_2-xLa_xV_0.90Cu_0.10O_5.5-α (x = 0, 0.10 and 0.20) and Bi_1.90Pr_0.10V_0.90Cu_0.10O_5.5-α were prepared by the standard ceramic synthesis technique. Electrical conductivity of the Bi_1.90La_0.10V_0.90Cu_0.10

A.A. Yaremchenko, V.V. Kharton, E.N. Naumovich… in Journal of Electroceramics (2000)

Article

Ceria-based materials for solid oxide fuel cells

This paper is focused on the comparative analysis of data on electronic and ionic conduction in gadolinia-doped ceria (CGO) ceramics as well as on the electrochemical properties of various oxide electrodes in ...

V. V. Kharton, F. M. Figueiredo, L. Navarro… in Journal of Materials Science (2001)

Article

Synthesis, Physicochemical Characterization and Ionic Conductivity of LaGa0.4Mg0.2M0.4O3−δ (M = Cr, Mn, Fe, Co)

Partial electronic and ionic conductivities, crystal structure, thermal expansion and infrared absorption spectra of the perovskite-type series, LaGa_0.40Mg_0.20M_0.40O_3−δ (M = Cr, Mn, Fe, and Co), have been studied...

V.V. Kharton, A.A. Yaremchenko, A.P. Viskup, G.C. Mather… in Journal of Electroceramics (2001)

Article

P-Type electronic conduction in CeO₂- and LaGaO₃-based solid electrolytes

Modifications of the e.m.f. and faradaic efficiency techniques, taking into account electrode polarization in the measuring cells, in combination with the use of electrodes having sufficiently high polarizatio...

V. V. Kharton, A. A. Yaremchenko, A. P. Viskup, F. M. Figueiredo, A. L. Shaulo… in Ionics (2002)

Article

Mixed conductivity of gadolinium titanate-based pyrochlore ceramics: The grain boundary effects

In order to reveal the role of grain boundaries on the ionic and electronic conduction processes, the transport properties of Gd_2−xGa_xTi₂O_7−δ (x=0.10–0.14) pyrochlore ceramics, pure and with SiO₂ additions, were ...

V. V. Kharton, F. M. B. Marques, E. V. Tsipis, A. P. Viskup, M. V. Patrakeev… in Ionics (2003)

Article

Mixed conductivity of zircon-type Ce_1−xA_xVO_4±δ (A=Ca, Sr)

Incorporation of alkaline-earth cations into the zircon-type lattice of Ce_1−xA_xVO_4+δ (A=Ca, Sr; x=0−0.2) was found to significantly increase the p-type electronic conductivity and to decrease the Seebeck coeffici...

E. V. Tsipis, V. V. Kharton, N. P. Vyshatko, A. L. Shaula, M. V. Patrakeev… in Ionics (2003)

Article

Mechanically-Activated Synthesis and Mixed Conductivity of TbMO_4−δ (M = Zr, Hf) Ceramics

Terbium hafnate and zirconate ceramics with submicron grain sizes were prepared via mechanically-activated synthesis. X-ray and electron diffraction and infrared (IR) absorption spectroscopy showed that TbZrO_4−δ ...

E.V. Tsipis, A.V. Shlyakhtina, L.G. Shcherbakova… in Journal of Electroceramics (2003)

Article

Oxygen ionic and electronic transport in Gd_2−xCa_xTi₂O_{7 −δ} pyrochlores

Oxygen ion transference numbers for Gd_2−xCa_xTi₂O_{7 −δ} (x=0.10–0.14) pyrochlore ceramics were determined at 973–1223 K by the modified e.m.f. and faradaic efficiency techniques, taking into account electrode polari...

V. V. Kharton, E. V. Tsipis, A. A. Yaremchenko… in Journal of Solid State Electrochemistry (2003)

Article

Oxidation of Dry Methane on the Surface of Oxygen Ion-Conducting Membranes

The surface exchange limitations of oxygen permeation through dense mixed-conducting membranes enhance membrane stability, enabling the operation of mixed conductors, such as La_0.3Sr_0.7Co_0.8Ga_0.2O_3-δ (LSCG) and L...

A.A. Yaremchenko, A.A. Valente, V.V. Kharton, E.V. Tsipis, J.R. Frade… in Catalysis Letters (2003)

Article

Stability and Thermal Expansion of Na⁺-Conducting Ceramics

An impedance spectroscopy study of sodium cation-conducting ceramics, including layered compounds Na_0.8Ni_0.4Ti_0.6O₂, Na_0.8Fe_0.8Ti_0.2O₂, Na_0.8Ni_0.6Sb_0.4O₂ (structural type O3), Na_0.68Ni_0.34Ti_0.66O₂ (P2 type), and ...

O.A. Smirnova, R.O. Fuentes, F. Figueiredo, V.V. Kharton… in Journal of Electroceramics (2003)

Article

Properties of CaTi_{1 − x}Fe _x O_{3 − δ} Ceramic Membranes

CaCO₃, TiO₂ and Fe₂O₃ were mixed in the appropriate stoichiometric quantities and calcined at 1100^∘C for 10 h. These powder mixtures were uniaxially pressed and sintered at temperatures ranging from 1350 to 1500_...

F. M. Figueiredo, M. R. Soares, V. V. Kharton… in Journal of Electroceramics (2004)

Article

Cellulose-precursor synthesis of nanocrystalline Ce_0.8Gd_0.2O_2−δ for SOFC anodes

Developments of intermediate-temperature solid oxide fuel cells (IT SOFCs) require novel anode materials with a high electrochemical activity at 800–1070 K. The polarization of cermet anodes, made of nickel, c...

E. V. Tsipis, V. V. Kharton, I. A. Bashmakov… in Journal of Solid State Electrochemistry (2004)

Article

Defect formation and transport in SrFe_1-xAl_xO_3-δ

Perovskite-related phases derived from SrFeO_3-δ are among known mixed conductors with highest oxygen permeability and are thus of interest as the ceramic membrane materials for oxygen separation and partial oxida...

A. L. Shaula, V. V. Kharton, M. V. Patrakeev, J. C. Waerenborgh, D. P. Rojas… in Ionics (2004)

Chapter and Conference Paper

Glass-Ceramic Sealants for SOFC-Based Systems

The studies of electrochemical, physicochemical and mechanical properties of glass-ceramic sealants, based on SiO₂-Al₂O₃-CaO-BaO and SiO₂-MgO-BaO systems, showed sufficient stability in contact with zirconia, lan...

V.V. Kharton, E.V. Tsipis, A.P. Carvalho… in Fuel Cell Technologies: State and Perspect… (2005)

Chapter and Conference Paper

Cellulose-Precursor Synthesis of Electrocatalytically Active Components of SOFCs and Mixed-Conducting Membrane Reactors

Developments of intermediate-temperature solid oxide fuel cells and electrocatalytic reactors require novel electrode and catalyst materials with high performance at 800–1100 K, low-cost processing technologie...

E.V. Tsipis, I.A. Bashmakov, V.V. Kharton… in Fuel Cell Technologies: State and Perspect… (2005)

Article

Transport and electrocatalytic properties of La_0.3Sr_0.7Co_0.8Ga_0.2O_3−δ membranes

Incorporation of gallium into the perovskite lattice of La_0.3Sr_0.7CoO_3−δ leads to increasing unit cell volume and to decreasing thermal expansion, total conductivity and oxygen permeability. At 973–1223 K, the ox...

V. V. Kharton, E. V. Tsipis, I. P. Marozau… in Journal of Solid State Electrochemistry (2005)

Article

Mössbauer Spectra and Catalytic Behaviorof Perovskite-like SrFe_0.7Al_0.3O_3-δ

Mixed-conducting SrFe_0.7Al_0.3O_3-δ (SFA) exhibits substantial catalytic activity towards partial oxidation of methane and can thus be considered as a component of monolithic ceramic reactors for synthesis gas gene...

V. V. Kharton, J. C. Waerenborgh, D. P. Rojas, A. A. Yaremchenko… in Catalysis Letters (2005)

Article

Development of oxygen ion conductors: One relevant tendency

In the past ten years a series of developments in the field of materials with dominant oxygen ion conduction introduced a variety of new systems. The most relevant aspect is a shift from ionic transport mechan...

F. M. B. Marques, V. V. Kharton in Ionics (2005)