Влияние стабилизирующих добавок на электропроводность керамики на основе ZrO2

Abstract

The creation of solid oxide fuel cells (SOFC) is one of the promising solutions to the problem of electricity supply. It is advantageous to use stabilized zirconium dioxide (ZrO2) as solid electrolytes in SOFC. In this paper, zirconium dioxide powders with additives of yttrium and scandium oxides (ZrO2–Y2O3, ZrO2–Sc2O3 and ZrO2–Y2O3–Sc2O3) were synthesized. Ceramic samples were obtained from the powders to study the effect of stabilizing additives on the conductive properties of zirconium dioxide. The addition of yttrium oxide Y2O3 in an amount of 8 mol. % contributed to the formation of a solid cubic solution of zirconium dioxide, and scandium oxide Sc2O3 increased the strength and conductive characteristics of the material. The definition of the conductive characteristics was carried out by impedance spectroscopy. Platinum paste was preliminarily applied by printing, which, when measured, ensured contact with the entire surface of the sample under study. It is shown that the addition of yttrium oxide contributes to the formation of a solid cubic solution of zirconium dioxide, and scandium oxide increases the strength (microhardness) and conductive characteristics of the material. Of interest is the simultaneous alloying of zirconium dioxide with scandium and yttrium oxides. The results of determining the properties of ceramic samples showed that the increase in electrical conductivity is more influenced by the addition of Sc2O3 compared with the addition of Y2O3. Stabilization without yttrium oxide leads to unstable conductivity values over time. A sample of ZrO2 – 1 mol%. – Y2O3 – 8 % mol. Sc2O3 has the potential to be used as an electrolyte in solid oxide fuel cells.