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In this paper, we are reporting an extensive characterization, by means of open circuit voltage measurements, of CeGdO, LaSrGaMgO, and LaMoWO oxide-ions and BaCeYO and BaCeZrYO proton-conducting electrolyte materials for solid oxide fuel cell (SOFC) applications. This simple and common technique, well known for a long time in the electrochemical study of solid oxide fuel cells, has been here proposed for the electrical characterization of these ceramic materials, in order to define their ionic transport numbers, the maximum voltage performances, the thermal and chemical stability, and also to suggest the ideal temperature range for different applications, as in the electrochemical devices, sensors, and SOFC field. In the paper, controlled and reproducible working conditions have been applied in a wide range of temperature, by means of ultrapure gas (H and O), under operational conditions found in real SOFC devices and, mainly, without the usual problems related to the chemical compatibility, the depolarization efficiency, and the high current density required to the electrode materials in the design of a more efficient SOFC device. [ABSTRACT FROM AUTHOR]

Thin films of LixMoyOz have been deposited on glass substrate in a one step chemical vapour deposition using a single source solid precursor. The films were characterized using Rutherford Backscattering Spectroscopy (RBS), X-Ray Diffractometry, Scanning Electron Microscopy (SEM), Impedance Spectroscopy (IS), van der Pauw conductivity measurement and Ultraviolet-Visible Spectroscopy. Results of the characterization showed that the films are dendritic, polycrystalline and semiconducting with an optical transition energy of 3.0 eV. IS characterization gave a semicircle in the complex impedance plot. The conductivity vs. temperature plot showed a transition at 450 °C and also a hysteresis. Analysis showed the film to be mixture of phases. [ABSTRACT FROM AUTHOR]

Dense fully stabilized cubic zirconia, sintered by the spark plasma sintering (SPS) method, was characterized through hardness, fracture toughness, and electrical impedance measurements. The effect of sintering temperature on hardness and fracture toughness was evaluated. Samples sintered at 1200 °C for 5 min, which had crystallite size of <100 nm, exhibited the highest hardness. Impedance measurements showed an increase in bulk contribution relative to grain boundaries as sintering temperature is increased. Calculation of the activation energy for conduction gave a value, 1.13 eV, in agreement with previously published results. [ABSTRACT FROM AUTHOR]

In this paper we describe about the synthesis of MgMn2O4 thin films by means of off-axis RF magnetron sputtering and their structural and morphological characterisation realised by means of X-ray diffraction (XRD), micro-Raman spectroscopy and Scanning Electron Microscopy (SEM). We explored different synthesis conditions, namely the substrate temperature, Ts, and the sputtering gas composition and we could observe that well-crystallised films are obtained at Ts = 500°C while the effect of the sputtering gas composition is to affect the structural properties of the films deposited. The thin films deposited always present a crystal structure less distorted with respect to the one of the target material. The possibility of synthesising films of low distorted spinels or even cubic ones may be an interesting way of preparing buffering layers for the growth of isostructural materials such as other spinels or pseudocubic perovskites. [ABSTRACT FROM AUTHOR]

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Copyright of Italian Journal of Neurological Sciences is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)