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Your search keyword '"Skubida, Wojciech"' showing total 22 results
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22 results on '"Skubida, Wojciech"'

5. Enhanced acceptor concentration, proton conductivity, and hydration in multicomponent rare‐earth ortho‐niobates.

Author

Dawczak, Arkadiusz, Skubida, Wojciech, Mielewczyk‐Gryń, Aleksandra, and Gazda, Maria

Subjects
*PROTON conductivity, *PHASE transitions, *DEUTERIUM oxide, *X-ray powder diffraction, *WATER temperature, *TRANSITION temperature, *RARE earth metals
Abstract

The structural properties of (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)1−xCaxNbO4−δ (x = 0–0.05) series have been studied by X‐ray powder diffraction at room temperature. The thermal properties were investigated using thermogravimetry, from which the concentration of proton defects was determined. Additionally, dilatometry studies were carried out, from which the thermal expansion coefficients and the phase transition temperature between low‐ and high‐temperature polymorphs were determined. In order to determine the electrical properties, the electrochemical impedance spectroscopy measurements under atmospheres of dry synthetic air and saturated with water vapor and heavy water at 300–800°C temperature range were performed. All the studied materials were single‐phase compositions and were stable in monoclinic I2/c crystal structure at room temperature. The water uptake studies revealed a small mass change under the switch from dry to humidified synthetic air atmospheres, suggesting the formation of proton defects. The phase transition from monoclinic to tetragonal crystal structure in the (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)1−xCaxNbO4−δ (x = 0–0.05) series occurs above 650°C. A small amount of calcium dopant increases the total conductivity in all tested atmospheres by two orders of magnitude, for example, from 0.34 μS cm−1 in La0.2Nd0.2Sm0.2Gd0.2Eu0.2NbO4 to 63.7 μS cm−1 in (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)0.95Ca0.05NbO4−δ at 700°C in humid synthetic air atmosphere. [ABSTRACT FROM AUTHOR]

Published
2024
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11. Properties of Barium Cerate-Zirconate Thin Films

Author

Winiarz, Piotr, primary, Covarrubias, Monica Susana Campos, additional, Sriubas, Mantas, additional, Bockute, Kristina, additional, Miruszewski, Tadeusz, additional, Skubida, Wojciech, additional, Jaworski, Daniel, additional, Laukaitis, Giedrius, additional, and Gazda, Maria, additional

Published
2021
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12. Optimization of proton conductors for application in solid oxide fuel cell technology

Author

Świerczek Konrad and Skubida Wojciech

Subjects
Environmental sciences, GE1-350
Abstract

Application of proton-conducting ceramic membranes in various electrochemical devices (e.g. SOFCs, SOECs) is considered as highly beneficial. Because of a unique transport mechanism associated with proton movement in oxide materials, designing and optimization, as well as practical application of such proton conductors is a challenge. In this work, apart from discussion of literature data, authors’ own results are provided, which are focused on material-related issues, including development of electrolyte and electrode materials exhibiting high proton conductivity.

Published
2017
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13. Properties of Barium Cerate Thin Films Formed Using E-Beam Deposition

Author

Campos Covarrubias, Monica Susana, primary, Sriubas, Mantas, additional, Bockute, Kristina, additional, Winiarz, Piotr, additional, Miruszewski, Tadeusz, additional, Skubida, Wojciech, additional, Jaworski, Daniel, additional, Bartmański, Michał, additional, Szkodo, Marek, additional, Gazda, Maria, additional, and Laukaitis, Giedrius, additional

Published
2020
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14. Novel Class of Proton Conducting Materials—High Entropy Oxides

Author

Gazda, Maria, primary, Miruszewski, Tadeusz, additional, Jaworski, Daniel, additional, Mielewczyk-Gryń, Aleksandra, additional, Skubida, Wojciech, additional, Wachowski, Sebastian, additional, Winiarz, Piotr, additional, Dzierzgowski, Kacper, additional, Łapiński, Marcin, additional, Szpunar, Iga, additional, and Dzik, Ewa, additional

Published
2020
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15. Antimony substituted lanthanum orthoniobate proton conductor – Structure and electronic properties

Author

Mielewczyk‐Gryń, Aleksandra, primary, Wachowski, Sebastian, additional, Witkowska, Agnieszka, additional, Dzierzgowski, Kacper, additional, Skubida, Wojciech, additional, Świerczek, Konrad, additional, Regoutz, Anna, additional, Payne, David J., additional, Hull, Stephen, additional, Zhang, Hangfeng, additional, Abrahams, Isaac, additional, and Gazda, Maria, additional

Published
2020
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21. Versatile Application of Redox Processes for REBaCoMnO5+δ(RE: La, Pr, Nd, Sm, Gd, and Y) Oxides

Author

Olszewska, Anna, Świerczek, Konrad, Skubida, Wojciech, Du, Zhihong, Zhao, Hailei, and Dabrowski, Bogdan

Abstract

Belonging to the not fully explored REBaCo2-xMnxO5+δsystem, a series of REBaCoMnO5+δ(RE: selected rare earth elements) oxides having perovskite-type structure is synthesized and studied in terms of their structural properties, oxygen content, stability, thermal expansion, and transport properties. Impact of RE3+on physicochemical properties of the compounds is derived, with smaller cations causing a decrease of the unit cell volume, lowering of the total oxygen content and thermal expansion, but also suppressing electrical conductivity. It is shown that a proper chemical modification enables to successfully utilize REBaCoMnO5+δin applications, in which redox processes associated with oxygen reduction/oxidation and transport determine the effectiveness of the working material. In particular, NdBaCoMnO5+δ(with larger Nd3+) shows good chemical stability in relation to Ce0.8Gd0.2O2−δand La0.8Sr0.2Ga0.8Mg0.2O3-δsolid electrolytes and moderate thermal expansion, 20.04(4)·10–6K–1in 300–900 °C. In symmetrical configuration with La0.8Sr0.2Ga0.8Mg0.2O3-δelectrolyte its cathodic polarization resistance is found to be only 0.036 Ω cm2at 900 °C, making it an excellent candidate cathode for solid oxide fuel cells. At the same time, YBaCoMnO5+δ(with small and cheap Y3+) delivers reversible oxygen storage capacity surpassing 3.4 wt % during the oxygen partial pressure swing process between air and 5 vol % H2in Ar at 500 °C.

Published
2018
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