Stability of the Structural and Transport Characteristics of (ZrO<sub>2</sub>)<sub>0.99−x</sub>(Sc<sub>2</sub>O<sub>3</sub>)<sub>x</sub>(R<sub>2</sub>O<sub>3</sub>)<sub>0.01</sub> (R–Yb, Y, Tb, Gd) Electrolytic Membranes to High-Temperature Exposure
Dmitrii Agarkov,
Mikhail Borik,
Galina Korableva,
Alexey Kulebyakin,
Irina Kuritsyna,
Nataliya Larina,
Elena Lomonova,
Filipp Milovich,
Valentina Myzina,
Polina Ryabochkina,
Nataliya Tabachkova,
Tatyana Volkova,
Denis Zakharov
Affiliations
Dmitrii Agarkov
Osipyan Institute of Solid State Physics RAS, Academician Osipyan Str., 2, 142432 Chernogolovka, Moscow District, Russia
Mikhail Borik
Prokhorov General Physics Institute of Russian Academy of Sciences, Vavilova Street, 38, 119991 Moscow, Russia
Galina Korableva
Osipyan Institute of Solid State Physics RAS, Academician Osipyan Str., 2, 142432 Chernogolovka, Moscow District, Russia
Alexey Kulebyakin
Prokhorov General Physics Institute of Russian Academy of Sciences, Vavilova Street, 38, 119991 Moscow, Russia
Irina Kuritsyna
Osipyan Institute of Solid State Physics RAS, Academician Osipyan Str., 2, 142432 Chernogolovka, Moscow District, Russia
Nataliya Larina
Institute of High Technologies and New Materials, National Research Ogarev Mordovia State University, Bolshevistskaya Street, 68, 430005 Saransk, Russia
Elena Lomonova
Prokhorov General Physics Institute of Russian Academy of Sciences, Vavilova Street, 38, 119991 Moscow, Russia
Filipp Milovich
Department of Materials Science, Moscow Polytechnic University, Bolshaya Semyonovskaya Street, 38, 107023 Moscow, Russia
Valentina Myzina
Prokhorov General Physics Institute of Russian Academy of Sciences, Vavilova Street, 38, 119991 Moscow, Russia
Polina Ryabochkina
Institute of High Technologies and New Materials, National Research Ogarev Mordovia State University, Bolshevistskaya Street, 68, 430005 Saransk, Russia
Nataliya Tabachkova
Prokhorov General Physics Institute of Russian Academy of Sciences, Vavilova Street, 38, 119991 Moscow, Russia
Tatyana Volkova
Institute of High Technologies and New Materials, National Research Ogarev Mordovia State University, Bolshevistskaya Street, 68, 430005 Saransk, Russia
Denis Zakharov
Department of Materials Science of Semiconductors and Dielectrics, National University of Science and Technology «MISIS», Leninskiy Prospect, 4, 119049 Moscow, Russia
The effect of long-term high-temperature annealing on the phase composition, local crystal structure, and oxygen-ion conductivity of SOFC membranes based on zirconium dioxide solid solutions was studied. Crystals with the composition of (ZrO2)0.99−x(Sc2O3)x(R2O3)0.01 (where x = 0.08–0.1; R-Yb, Y, Tb, Gd) were obtained by the method of directed melt crystallization in a cold crucible. The crystals were annealed in air at a temperature of 1000 °C for 400 h. The phase analysis of the crystals before and after annealing was studied by X-ray diffractometry and Raman spectroscopy. The study of the ionic conductivity of the crystals was carried out by the method of impedance spectroscopy in the temperature range 400–900 °C. It has been shown that when various rare earth cations (Yb, Y, Tb, and Gd) are used, the maximum conductivity is observed for the compositions (ZrO2)0.91(Sc2O3)0.08(Yb2O3)0.01, (ZrO2)0.89(Sc2O3)0.1(Y2O3)0.01, (ZrO2)0.90(Sc2O3)0.09(Tb2O3)0.01, and (ZrO2)0.89(Sc2O3)0.1(Gd2O3)0.01. At the same time, these crystals have a highly symmetrical pseudocubic structure, which is retained even after crystal annealing. At comparable concentrations of Sc2O3, the conductivity of crystals decreases with an increase in the ionic radius of the rare earth cation. The high-temperature degradation of the conductivity is also discussed depending on the type of rare earth oxide and the concentration of scandium oxide.
