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The average number of incoming calls determining the amount of load on the Valdai emergency care station (ECS) in the Novgorod region is estimated. Calculations of the required number of brigades were carried out, 3 models of the functioning of the ECS were proposed. Possible financing schemes for the work of the ECS have been identified. A comparison of the necessary costs for staff remuneration with two possible financing schemes was carried out. The proposals on the organization of the work of the ECS are formulated.

Ce0.8R0.2O2–a (R = Y, Sm, Tb) (further Се20R) submicron barrier layers, which were obtained by the dip-coating method on a YSZ (ZrO2 + 9.5 mol.% Y2O3) solid electrolyte to prevent the chemical interaction between YSZ and the La2NiO4+δ-based cathode material, were studied. The final thermal treatment of the barrier layers was performed at 1200 °С. A porous composite of the La2NiO4+δ-Ce0.8Sm0.2O2–а composition with the LaNi0.6Fe0.4O3 collector layer served as the cathode. The polarization characteristics of the cathodes were studied by impedance spectroscopy for both the uncoated electrolyte and the electrolyte with Се20R (R = Sm, Tb, Y) thin-layer coatings of various thicknesses. The impedance spectra were analyzed using the DRT method. Even single-layer coatings (≈200 nm) were found to prevent the chemical interaction between the electrode and the electrolyte and to greatly increase (by 5.5–6 orders of magnitude) the electrode polarization conductivity.

Background . Prostate cancer (PCa) is one of the most common malignancies. The gold standard of PCa diagnostics is morphological examination of prostate tissues obtained using 10-12-core biopsy. However, the number of false-negative results and detected clinically insignificant forms of cancer remain high. Magnetic resonance imaging (MRI) is the most sensitive and specific method of radiation diagnosis of PCa. The use of MRI data for prostate biopsy (fusion-biopsy) increases the accuracy of this procedure. Objective : to increase the accuracy of PCa diagnostics using targeted pararectal prostate biopsy guided by computed tomography (CT)/MRI. Materials and methods . A total of 95 patients underwent CT/MRI-guided targeted pararectal biopsy between March 2015 and March 2020. The mean level of prostate specific antigen (PSA) was 13.7 ± 12.6 ng/mL. All men were found to have 1 to 3 lesions with a PI-RADS score between 3 and 5. Patients were divided into 4 groups: 1 st group (n = 33) included patients in whom transrectal access was impossible; 2 nd group (n = 22) included patients with suspected local recurrence of PCa after brachytherapy; 3 rd group (n = 28) included patients with a negative result of primary biopsy, but with growing PSA level; 4th group (n = 12) included patients who preferred targeted biopsy. We performed targeted biopsy of each suspicious lesion according to MRIscans. Then we performed ‘blind’ systematic 10-14-core biopsy, where we did not take into account the location of suspicious foci and they could be, therefore, accidentally used for sample collection for the second time. Results . Histological examination revealed PCa in 71 out of 95 patients (74.7 %): in 27 out of 33 in 1 st group (81.8 %), in 19 out of 22 in 2 nd group (86.4 %), in 17 out of 28 in 3 rd group (60.7 %), and in 8 out of 12 in 4 th group (66.7 %). In 21 patients (29.6 %), PCa was diagnosed only in samples obtained using targeted biopsy; in 9 patients (12.7 %), PCa was diagnosed only in samples after systematic biopsy; in 41 patients (57.7 % PCa was detected by both targeted and systematic biopsy. Clinically significant cancer (Gleason score ≥7) was diagnosed in 84.5 % of cases after targeted biopsy and in 70.4 % of cases after systemic biopsy. Conclusion . CT/MRI-guided prostate fusion biopsy increases the accuracy of PCa diagnostics by additional detection of clinically significant tumors, including those in patients in whom the rectal access is impossible.

The method of electrochemical impedance is used to study the polarization conductivity of porous platinum electrodes in the Pt|YSZ|Pt cells over the temperature range from 500 to 700°C in air. Electrodes are impregnated with microquantities of praseodymium oxide PrOx (from 10–4 to 0.1 mg/cm2) by the impregnating them with praseodymium nitrate solution, with further thermal treatment: slow heating (50°С/h) up to 850°C. This processing resulted in the formation of the praseodymium oxide nanofilm on the electrolyte surface. The introducing of PrOx, even in an amount of 10–4 mg/cm2, is found to significantly increase the electrode polarization conductivity. Analysis of the electrochemical impedance spectra was performed by DRT (distribution of relaxation times) method, which revealed a change of the rate-determining stage of the electrode process in the concentration range of praseodymium oxide from 1 × 10–3 to 3.3 × 10–3 mg/cm2. The studied electrodes are discussed in terms of the island model of dense-oxide-PrOx-electrodes in which platinum plays the role of the current collector.

Ceramic Sr2Ce0.95Yb0.05О4 samples have been synthesized by the Pechini process and their electrical conductivity has been determined as a function of temperature (300–900°C), and (40–2500 Pa) using four-probe and impedance measurements. In air at high temperatures, the material is a mixed oxygen–hole conductor, with predominantly oxygen-ion conductivity. At reduced temperatures, proton conductivity prevails, with σ ~

An analysis of primary literature sources shows that there is only one reliable report on the observation of the cubic ZrO2 phase by the X-ray method under oxidizing conditions. This phase is observed at temperatures not lower than 2500°C. All other reports on the observation of a phase transition around 2300°C are reliable only in relation to the existence of a transition at this temperature, but this transition is to the t' tetragonal phase rather than to the cubic one. The conclusion is that the following four polymorphic modifications are present in ZrO2 under the standard pressure: monoclinic (m), two tetragonal (t and t'), and cubic (c) phases that are converted into each other with an increase in the temperature.

The total, bulk, and grain boundary conductivities of proton-conducting zirconates of general formula AZr0.95Sc0.05O3 – α (AZS), where A = Ca, Sr, Ba, are measured in air with different humidity levels. The conductivity is measured using the four-probe dc method (600–900°C) and impedance spectroscopy (30–800°C). The impact of humid atmosphere on the total, bulk, and grain boundary conductivities of the AZS system is studied at different humidity levels: $${{p}_{{{{{\text{H}}}_{{\text{2}}}}{\text{O}}}}}$$ = 0.04, 0.61, and 2.5 kPa. Humidity is found to have a considerable effect on the conductivity of our CaZS and BaZS at lower temperatures, suggesting the likelihood of hydronium ion-mediated transport.

Porous platinum electrodes on ZrO2 + 10 mol % Y2O3 solid electrolyte (YSZ) are activated by Tb1 − xCexO2 − α (x = 0; 0.15; 0.33; 0.5; 1.0) mixed oxides by impregnation, and their polarization characteristics are studied. The activation is carried out under the conditions that an oxide activator nanofilm forms on the electrolyte surface as a result of heat treatment of the electrode. The activation is performed by impregnating the electrodes with low-concentrated alcohol solution of terbium and cerium nitrates (1.5% as recalculated to the oxides) and subsequent slow heating (≤50°C/h) to 850°C. An average thickness of the film on the electrolyte after a single activation (≈0.1 mg oxides/cm2) is estimated at 10–20 nm. The electrodes of Pt|YSZ|Pt cell activated by Tb1 − xCexO2 − α films are studied by the impedance method in the oxidative and reductive atmospheres in the range of 700 to 500°C. The polarization conductivities of the activated electrodes increase by 2–3 orders of magnitude. The studied electrodes are discussed within the model of compact oxide electrodes, where platinum plays the role of collector. The advantage of these electrodes is that they can work both in the oxidative and reductive conditions. According to the aggregate of the properties, Tb1 − xCexO2 − α compounds at x = 0.3–0.5 are recommended for activation.

Research into the synthesis of oxide materials exhibiting high ionic conductivity values allows these materials to be used for the fabrication of such high-temperature electrochemical devices as fuel cells, gas sensors, electrolyzers, etc. A focused interest in the physical and chemical properties of oxide proton conductors is driven by the phenomenon of proton transfer in those solids, where hydrogen is not a structural unit. LaScO3-based materials are considered to be promising for high-temperature engineering due to their bulk conductivity at low temperatures, chemical resistance and mechanical strength as compared to widely-used proton-conducting cerate- and zirconate-based electrolytes. A series of experiments was performed to compare the properties of La1-xSrxScO3-α (х = 0.05; 0.10) solid proton-conducting electrolytes synthesized using different methods. An alternative combustion method that does not apply nitrates as precursor materials is proposed. This method allowed ceramics with a density greater than 98% of theoretical to be obtained. A detailed qualitative and quantitative evaluation was performed at different synthesis stages using the methods of X-ray diffraction, scanning electron microscopy, X-ray fluorescent and atomic emission spectroscopy. The structure parameters of La1-xSrxScO3-α were determined by full-profile Rietveld X-ray diffraction analysis. The thermal expansion and electrical conductivity of La1-xSrxScO3-α (x = 0.05, 0.10) materials having various densities were studied in oxidizing and reducing atmospheres under changes in the temperature and humidity of the gas phase. The contribution of bulk and grain boundary conductivities was assessed using the impedance method. Both conductivities are established to exhibit the same activation energy for the materials with a density of 94–98% of the theoretical value. The high porosity of the materials (30%) is shown to adversely affect the total conductivity, with the bulk conductivity remaining almost at the same level. A bridge model based on semi-coherent boundaries is proposed for explaining a low grain boundary conductivity in proton electrolytes having a low-symmetry crystal lattice.

The ionic (proton and deuteron) conductivity of the system CaZr1 – xScxO3 – α (x = 0.03–0.20) is studied experimentally in H2 + H2O + N2 and D2 + D2O + N2 reducing atmospheres at pH2O = pD2O = 3.2 kPa and in the temperature range of 600–900°C. This system exhibits a considerable H/D isotopic effect in conductivity, and its magnitude is estimated. Using theoretical elaborations, we also estimate the magnitude of the thermodynamic isotope effect in the solubility of H2O/D2O in the considered system under reducing conditions.

The development of solid oxide fuel cells (SOFC) is one of the priority directions for the creation of alternative energy sources. High operating temperatures of these devices are lead to the complexity of the constructions and active diffusion processes between the functional materials. The use of thin-film proton electrolytes is a promising way to reduce the operating temperature of SOFC, while the conductivity level and, as a result, the effective power, may be maintained due to the smaller thickness of the film. Based on LaScO3 proton-conducting oxides with a perovskite structure, having high chemical stability to water vapor, are promising proton electrolytes for SOFC, but they are poorly studied in the form of thin films. Lanthanum-strontium manganite is one of the most common materials for the SOFC cathode. The aim of this work is to study the effect of the La0.6Sr0.4MnO3-α cathode substrate composition on the properties, including the electrical conductivity of La1-xSrxScO3 (0.01, 0.05 and 0.10) thin-film proton electrolytes, obtained by simple centrifugation of the film-forming solution. The properties of La1-xSrxScO3 in the form of ceramic and thin-film samples are compared. The experiment showed that the films La1-xSrxScO3 at 5 ÷ 30-fold deposition on cathode substrates form continuous coatings with a grain size of 50–200 nm, which do not contain transverse pore. These results have a fundamental importance for the development of SOFC with ultra-thin film electrolyte on a supporting electrode. It is established that under dry and wet air the electrical conductivity of La0.6Sr0.4MnO3-α/La1-xSrxScO3/Pt cells is bulk conductivity and it rises with increasing atmospheric humidity, which indicates an increase in the contribution of proton conductivity. In this case, the grain-boundary resistance of the material and the polarization resistance of the electrodes are practically not realized. The conductivity of LSS films is 1–2 orders of magnitude higher than the bulk conductivity of ceramic samples of similar composition and has a low activation energy. The observed differences in the conductive properties of films are explained by the interaction of related perovskites of the scan date and lanthanum manganite. The data obtained may be of interest to specialists in the fields of hydrogen energy, electrochemistry, materials science, the development of electrochemical devices: sensors, fuel cells.

Comparative impedance measurements of electric conductivity of nominally undoped yttria are carried out for samples with sharply differing morphologies, namely, single crystals and porous ceramics (with a density of 67%) over a 980–350°С temperature range in air atmosphere of different humidity (рН2О= 40–3000 Pa). Dilatometric analysis of possible structure changes is carried out. The effects of uncontrolled impurities on the yttria defect structure are analyzed.

Electrical conductivity (at 460–990°С) and ion and proton transference numbers (at 550–950°С) of nominally undoped BaCeO3 have been studied as dependent on temperature, pO2 (2.1 × 10–4 to 10–15 Pa), and pН2O (40–2340 Pa). For determining the defect model, small additives of aliovalent dopants Nd3+ (up to 1 at %) and Ta5+ (up to 0.5 at %) were used. The effect of cationic nonstoichiometry of barium cerate on the electrical conductivity and reaction with the gas phase has been considered. Charge transfer in ВаСеО3 is explained using the model of defect formation in the reaction of ВаСеО3 with the gas phase.

Technique was developed for fabrication of a supporting thin-walled gas-tight ZrO2–Y2O3 electrolyte base of strict configuration for tubular solid-oxide fuel cells. The technique includes a plasma-assisted deposition and vacuum impregnation with salt solutions, followed by a thermal treatment. The properties of plasma-ceramic solid electrolytes based on cubic and tetragonal (t') forms of ZrO2 and the same electrolytes modified with small additions (0.5 wt %) of aluminum oxide were examined. The phase composition, electrical conductivity, thermal expansion, and stability of the materials synthesized were studied. A high stability in time of the tetragonal t'-solid electrolytes was noted, which opens up prospects for their application in solid-oxide fuel cells.

Single-phase solid solutions based on proton-conducting oxide La0.9Sr0.1ScO3–δ (LSS) and containing from 0 to 47 at % Fe in the scandium sublattice are synthesized by the method of combustion with ethylene glycol at 1400°C. Their electric conductivity, thermal expansion, and parameters of orthorhombic lattice are studied. Anomalies in the temperature dependences of conductivity and thermal expansion associated with dissolution of water vapor in the oxides are observed, as well as the breaks in concentration dependences of orthorhombic lattice parameters in the region of low iron contents. The introduction of even small amounts of iron oxide (up to 3 at % Fe) into LSS leads to disappearance of protonic conductivity. The factors responsible for the appearance of defective structure and its model explaining this phenomenon are discussed.

The structure of dry and hydrated perovskite La 0.9 Sr 0.1 ScO 3 − δ has been studied by means of X-ray and neutron powder diffraction methods. Preferable positions for oxygen vacancies and deuterons in the oxide have been determined. Thermodynamics of water vapour uptake and transport phenomena have been experimentally investigated at p H 2 O = 0.24 atm and p O 2 = 0.18 atm in the temperature range from 300 to 950 °С. The enthalpy and entropy of hydration reaction have been calculated. The oxidation enthalpy for two possible mechanisms of hole transfer (band conduction and small polaron hopping) have been estimated. The electrical conductivity has been investigated by means of impedance spectroscopy measurements in the temperature range from 500 to 900 °С and at the oxygen partial pressures of 10 − 20 atm p O 2 0.9 Sr 0.1 ScO 3 − δ oxide was found to be a pure protonic conductor at temperatures below 600 °С under reducing conditions.

The characteristics of porous Pt/YSZ (ZrO2 + 10 mol % Y2O3) electrodes activated with small amounts of either oxides of rare-earth elements (REE) of the cerium subgroup (CeO2, PrO x , TbO x ) or a mixed oxide with the Сe2Tb4O11 composition by the procedure of impregnating the electrodes with ethanol solutions of REE nitrates and subsequent heating at 850°С are studied by the impedance method. The studies are carried out for those cases where the REE oxides after thermal treatment form a film on the electrolyte and also where no activator film is formed. The characteristics of films and activated electrodes are compared. Film-activated Pt/YSZ electrodes are discussed within the framework of the model of compact oxide electrodes.

The total, proton, and oxygen conductivities in the CaZr1–x Sc x O3–α system (x = 0.03–0.20) were studied experimentally in the reductive atmospheres H2 + H2O + N2 in the temperature range 600–900°C. The electric conductivity and the transport numbers of ions and protons were measured using the direct current four-probe method and the EMF method with oxygen and water vapor concentration cells, respectively. The materials under study are pure proton-conductive below 700°C in these atmospheres; at higher temperatures, a pronounced contribution of oxygen conductivity appears. The isotherms of the total and partial conductivities are symbatic and have a maximum between x = 0.05 and x = 0.10, which correlates with the position of the boundary of the single-phase state.

The conductivity of single-phase ceramic materials based on proton-conducting perovskite La0.9Sr0.1ScO3–α containing from 0.3 to 47 at % Fe in the scandium sublattice has been studied. Synthesis has been performed by burning with ethylene glycol. Measurements have been carried out by the four-probe (500–900°C) and impedance (100–500°C) methods in oxidizing and reducing atmospheres, as well as at different pressures \({p_{{O_2}}}\) (2.1 × 104–10‒15 Pa) and \({p_{{H_2}O}}\) (0.04–2.5 kPa). Substitution of scandium with iron significantly decreases the proton conductivity.

The fabrication, the characterization and the electrochemical performance of a solid electrolyte film of Y-doped CaZrO3 deposited on a porous SrTi0.8Fe0.2O3-δ substrate are studied in the present work. A dense 6-μm-thick film of the electrolyte is prepared by multi-step chemical solution deposition. Phase purity, concentrations of the elements and microstructure of the film are characterized by means of X-ray diffraction, energy-dispersive X-ray spectroscopy and scanning electron microscopy. The results indicate interdiffusion between the film and the substrate. For the electrochemical characterization of the electrolyte film a gas concentration cell Pt/STF/CZY-film/Pt is fabricated. Open circuit voltage (OCV), impedance spectra (EIS) and current-voltage characteristics are measured at the oxygen concentration cell in the temperature range from 500 to 600 °C. The ionic transport numbers in the electrolyte film determined from the impedance and OCV data are found to vary within 0.93–0.97 interval. This is significantly higher than the ratio Em/EN between the measured OCV value (Em) and the theoretical EMF value (EN), which determines the transport numbers in the case of non-polarizable electrodes. It is concluded that this difference is caused mainly by the high polarization resistance of the cell.

The method of impedancemetry is used to study electrochemical activity of platinum electrodes in contact with the solid electrolyte of YSZ (ZrO2+10 mol % Y2O3). Electrodes are activated by small additives of pradeodymium oxide PrOx (0.1–0.3 mg/cm2) by their impregnation by praseodymium nitrate solution with the further thermal treatment at 850°C and are studied in the cases when PrOx forms a film on the electrolyte and when no activator film is formed. The effect of the number of electrode activations on the electrochemical activity of platinum electrodes is studied.

Partial (ionic, proton, and hole) conductivities of oxides CaZr1–xScxO3–α(x = 0.03–0.20) with the perovskite structure in air atmosphere have been studied as functions of temperature in the range of 600–900°C and partial water-vapor pressure in the range of \({P_{{H_2}O}}\)= 40–2500 Pa. The influence of the humidity of the atmosphere on the relative change in the concentration of oxygen vacancies as a function of temperature has been estimated.

A praseodymium oxide film has been produced by dip-coating an alundum (Al2O3) substrate in an ethanolic solution of praseodymium nitrate, followed by heat treatment, and ceramic praseodymium oxide samples have been prepared for comparison. The materials have been characterized by simultaneous thermal analysis (STA), X-ray diffraction, scanning electron microscopy, and dilatometry. The electrical conductivity of the films and ceramic samples has been measured as a function of temperature by a standard fourprobe dc technique at different air humidities. Phase transitions of the samples have been detected by STA, dilatometry, and electrical conductivity measurements.

The effect of doping on the transport properties of solid electrolytes La0.9Sr0.1ScO2.95 + x FeO1.5 (x = 0.1–15.0 wt % FeO1.5) has been elucidated by investigating the electrical conductivity of these materials by the four-probe method and the impedance method as a function of external parameters, namely, temperature T (150–900°C), oxygen partial pressure $p_{O_2 } $ (0.21 × 104–10−15 Pa), and humidity $p_{H_2 O} $ (0.04–2.35 kPa). Samples of the solid electrolytes have been investigated using X-ray powder diffraction, electron microscopy, and Mossbauer spectroscopy.

Phase composition, thermal expansion, and electrical conductivity were studied for three-component solid solutions of the system HfO2–Sc2O3–Y2O3, containing 7–10 mol % Sc2O3 and 1–4 mol % Y2O3, which corresponds to the maximum-conductivity region. The electrical conductivity was measured in two ways: by the four-probe mode in the dc mode and by impedance spectroscopy. A solid electrolyte of composition HfO2 + 8 mol % Sc2O3 + 2 mol % Y2O3 was obtained, close in conductivity to the solid electrolyte composed of ZrO2 + 8 mol % Y2O3.

Room-temperature measurements of diffusion coefficients for deuterium in proton conductors La0.9Sr0.1ScO3 -δ and BaZr0.9Y0.1O3 -δ which contain dissolved H2O vapor have been performed. The concentration of oxygen structure vacancies in oxides after treatment in vapor was close to zero. A diffusion source of deuterium was created by ion implantation; measurement of the concentration–distance distribution of deuterium in samples was performed in situ during implantation. The NRA technique and 2H(d,p)3H reaction at an energy of the incident beam of 650 keV were used. For the initial and boundary conditions of the diffusion problem which were realized in the work, a solution of the inhomogeneous Fick equation was obtained. Using the technique developed, measurements of the diffusion coefficients for hydrogen in proton conductors were for the first time performed directly. For the BaZr0.9Y0.1O3 -δ oxide, the directly gained values of diffusion coefficients agree rather well with those obtained from the proton conductivity with the use of Nernst–Einstein equation.

CaZr0.9Y0.1O3−δ (CZY) films were fabricated by chemical solution deposition (CSD) from ethanol-based liquid solutions. The films were deposited on single crystals of yttria-stabilized zirconia (YSZ) in (100), (110) and (111) crystallographic orientations. The structural, mechanical and electrical properties of the films have been studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and nanoindentation and impedance spectroscopy methods. XRD and SEM results have shown that the films were polycrystalline. Effect of the substrate orientation on the microstructural, mechanical and electrical properties of CZY films has been examined. The films deposited on (110)-substrates consist of the largest grains; show the highest values of hardness and electrical conductivity. Conductivity of CZY film on (110)-substrates increases with rise in humidity which proves proton transport in the films.

The total conductivity of CaZr1 − x Sc x O3 − α (x = 0.01–0.20) materials has been measured by the four-probe dc method at temperatures from 600 to 900°C in humid air (pH2O = 40–2500 Pa), and CaZr0.95Sc0.05O3 − α has been characterized by impedance measurements. The ion and proton transport numbers in CaZr0.95Sc0.05O3 − α have been determined as functions of air humidity. The observed anomalies in the temperature dependences of electrical conductivity for the materials studied have been compared to dilatometry data and interpreted in terms of structural changes in their oxygen sublattice.

Total electrical conductivity and contributions of different charge carriers such as oxygen ions, protons, electrons and holes in CaTi1 − xFexO3 − δ (x = 0–0.5) were measured as functions of temperature, oxygen partial pressure and iron content. Total electrical conductivity measurements were made by means of the four-probe dc technique. Partial electronic conductivity was studied by the Hebb–Wagner polarization method. Transport numbers of oxygen ions and protons in CaTi1 − xFexO3 − δ were measured by the EMF method. It has been shown that CaTi1 − xFexO3 − δ is a mixed oxygen-ion and electronic conductor at small iron concentrations, and it is a predominantly electronic conductor at large iron contents. Proton conductivity of CaTi1 − xFexO3 − δ is negligibly small. Ambipolar conductivity of CaTi1 − xFexO3 − δ was calculated. With known ambipolar conductivity a profile of the oxygen chemical potential inside CaTi1 − xFexO3 − δ under applied oxygen partial pressure gradient can be figured out.

A model is proposed to calculate the residual thermomechanical stresses in the layers of a tube solid oxide fuel cell (SOFC) that are caused by the difference between the linear thermal expansion coefficients of these layers. The distributions of the residual stresses in the cell layers that appear during the production of SOFC and under operating conditions are determined, and the regions of probable failure in the cell are revealed.

The hydrogen content in CaZr1 − x Sc x O3 − x/2 (x = 0.00–0.20) and BaZr0.9Y0.1O3-α (for comparison) was studied by powder nuclear microanalysis. The samples were saturated with heavy water (D2O) vapors at 350 and 400°C in air. The chemical expansion of the CaZr0.95Sc0.05O3-α and BaZr0.95Y0.05O3-α samples at 700°C was measured at different water vapor pressures. A model was suggested to explain the lowered hydrogen content in oxides based on CaZrO3.

The across-plane electrical conductivity of the proton-conducting SrZr0.95Y0.05O3 − δ thin films fabricated by chemical solution deposition on single-crystalline ZrO2 doped by 10 mol% of Y2O3 (YSZ) substrates was investigated using impedance spectroscopy. The average grain size of the films was found to increase considerably with thermal treatment. This change in grain size has a strong effect on the electrical behavior of films. Our results show that the electrochemical performance of the cell is strongly affected by the potential difference at the film/substrate interface. Coarse-grain film microstructure was proved to be preferable for the reduction of both the film resistance and interfacial barrier.

The phase composition and the total and partial conductivities of ceramic samples LaSc1 − xO3 − α (x = 0−0.1) are studied as a function of the air humidity (pH2O = 0.04−2.35 kPa) and the oxygen partial pressure (−15 ≤ logpO2 ≤ −0.68) in a wide temperature range from 100 to 900°C as well as their thermal expansion.

Transport numbers of ions and protons are measured on ceramic samples of La1 − x Sr x ScO3 − α (x = 0.01–0.15); partial conductivities (hole, proton, and oxygen-ion) are determined in the temperature range of 500–900°C at pH2O = 0.04–2.35 kPa and pO2 from air to 10−15 Pa.

This study surveys the results obtained at the Institute of High Temperature Electrochemistry, Ural Branch, Russian Academy of Sciences on the physicochemical properties of proton-conducting materials based on LaScO3 and analyzes the literature data.

The phase composition was studied and overall conductivity of oxides La1 − xSrxScO3 − α (x = 0.01−0.20) was measured as dependent on air humidity (pH2O = 0.04−2.35 kPa) in the temperature range from 100 to 900°C. The samples were synthesized in air at 1600°C. They are single-phase, with a perovskitetype structure with orthorhombic distortions and the density of 94–99%. The conductivity measurements were carried out using the impedance technique and four-probe dc technique. The contributions of bulk and grain boundary resistances were determined, effective conductivity activation energies were calculated.

CaZrO3 films are studied that were obtained on ceramic supports of solid electrolyte of ZrO2 + 9 mol % Y2O3 (YSZ, yttria stabilized zirconia) from alcohol solutions of zirconium oxychloride and calcium nitrate using the method of dipping with the following drying and annealing. The thickness and morphology of films depend on the concentration of the film-forming solution. Vickers microhardness of the CaZrO3 films was determined. The impedance spectroscopy method was used to study conductivity of films at the temperature of 400–600°C by comparison of impedance spectra of clean supports and supports with a film coating.

The effect of Sc-sublattice defectiveness, at the acceptor doping or making it deficient in cations, on hydrogen content in and electrophysical properties of La0.9Sr0.1ScO3 is studied.

A novel method for studying the H/D isotope separation effect in the “nonstoichiometric oxide-gas” system is suggested. The theoretical scheme of this method is represented for doped perovskites of the ABO3 family, but this approach is also applicable to other compounds where the solubility of hydrogen is determined by the content of oxygen vacancies. The suggested approach is used to determine the H/D isotope effect in hydrogen solubility from the experimental data for proton-conducting oxides. The measurements have been taken using the nuclear microanalysis of fine-grain BaZr0.9Y0.1O3 − y powders. The method is based on the study of the products of the 2H(d, p)3H nuclear reaction. The observed pronounced isotope effect is in quantitative agreement with our theoretical predictions.

Ionic, proton, and oxygen conductivities are measured as functions of air humidity (pH2O = 0.04−3.57 kPa) in the BaZr1 − xYxO3 − α system (x = 0.02−0.15) over the temperature range 600–900°C. The important result is obtained that dissolved water vapor determines not only proton transport, but also the overwhelming part of oxygen transport in BaZr1 − xYxO3 − α.

The surface of ceramic electrolyte ZrO2 + 9 mol % Y2O3, hereinafter referred to as YSZ (abbreviated yttria stabilized zirconia), was modified with 0.1 to 0.2 μm oxide films of ZrO2, Y2O3, and YSZ (same composition as substrate) by dip coating in alcohol solutions of the relevant salts and further annealing. The results of scanning electronic microscopy and X-ray diffraction evidence epitaxial film growth. By means of impedance spectroscopy at the temperatures of 500 to 600°C, the effect of YZS electrolyte surface modification with ZrO2, Y2O3, and YSZ films to the polarization resistance of silver electrode was studied.

The ion and proton transfer numbers were measured by emf method in La1 − xSrxSc1 − yMgyO3 − α (x = y = 0.01–0.20) system in reducing hydrogen-containing atmosphere in the range of temperatures from 630 to 920°C and pH2O from 0.61 to 2.65 kPa. Total ionic, proton, and oxygen conductivities of this system was measured as well. The electroconductivity measurements were carried out vs. pO2 (from air to 10−14 Pa).

Proton and deuteron conductivities in the BaZr1 − x Y x O3 − δ system (x = 0.02–0.2) are investigated experimentally over the temperature range 600–900°C in reducing H2/H2O and D2/D2O atmospheres with pH2O = pD2O = 3.15 kPa.

The conductivity and ion and proton transfer numbers were measured in La1 − xSrxSc1 − yMgyO3 − α system (x = y = 0.10–0.20). The partial conductivities (total ion, proton, oxygen, hole) and their effective activation energies were calculated. The measurements were carried out in air with respect to humidity (pH2O = 0.04−2.65 kPa) within the temperature range from 630 to 920°C.

The total and hole (p-type) conductivities are measured in the BaZr1 − x Y x O3 − α system (x = 0.02−0.20) in the temperature range of 600–900°C as a function of air humidity (pH2O = 0.04−3.17 kPa). The model of defect formation in BaZr1 − x Y x O3 − α oxides in the presence of water vapor is discussed and the literature data are analyzed.

The described method for synthesis of proton-conducting ceramics BaZr0.9Y0.1O3 − α at the temperature of 1850°C from mixture of barium carbonate and zirconium-yttrium hydroxides enabled to prepare high-density translucent specimens. According to powder diffraction data, the synthesized ceramics consists of single phase and has the cubic perovskite structure with the elementary cell parameter a = 0.42009 ± 0.00004 nm. The electrophysical properties of the synthesized ceramics were measured. The conductivity of such high-density specimens was shown to excel by an order of magnitude the conductivity of porous (80% relative density) material.

Highly compact (99%) solid electrolyte Ce0.8Gd0.2O1.9 with submicron (0.3 μm) grains is synthesized. The dilatometric (20–850°C) and conductivity (180–350°C) measurements are performed on the electrolyte in air and as a function of the partial oxygen pressure $$p_{O_2 } $$ (0.21−1×10−25 atm) at 600, 700, and 800°C. An inflection is found in the temperature dependences of the thermal coefficient of linear expansion and conductivity (impedance measurements) at ∼230°C, which is the evidence for a phase transition. The activation energies for conduction in the grain bulk and boundaries differ only slightly, indicating that the grain boundaries’ resistance is caused not by the precipitation of the second phase at the boundaries, but most probably by the presence of intergranular nanopores. The dilatometric measurements confirm a significant increase in the linear dimensions of Ce0.8Gd0.2O1.9 in the reducing atmospheres with a parallel increase in its electron conductivity. The electron conductivity and specific elongation increase proportionally to $$p_{O_2 }^{ - 1/4} $$ at all temperatures. The $$p_{O_2 } $$ values, at which the transport numbers of ions t i = 0.5, are determined. They are 10−22.5, 10−20, and 10−18 atm at 600, 700, and 800°C, respectively.

A complex investigation of solid electrolytes Ce1−x Sm x O2−δ (x = 0.10−0.30) is performed in a broad temperature interval by methods of x-ray diffraction analysis, electroconduction, dilatometry, differential scanning calorimetry, and thermogravimetry. Ceramic technology is used for the synthesis. The density of the obtained specimens is no lower than 95%. The dilatometry measurements reveal the presence of singularities in the curves obtained at temperatures in the region of 180–230°C, which may be ascribed to a phase transition of the type order-disorder of hypothetical phase Ce7SmO15.5. The electroconduction and dilatometry methods also point to the presence of singularities in the temperature dependences in the temperature interval extending from 800 to 870°C.