BaZr_1-xY_xO₃ is an attractive electrolyte material for low operating temperature SOFCs and SOECs because of its high proton conductivity at temperature less than 600 ^oC and good chemical stability under CO₂ and steam atmospheres. However, its high synthetic temperature more than 1100 ^oC and the high sintering temperature more than 1,600 ^oC to get a dense electrolyte membrane cause mismatch of the shrinkage behavior and reaction with other SOFC or SOEC component materials at the fabrication process.

Therefore, in this paper, reducing the synthesizing temperature of BaZr_1-xY_xO₃ powders by freeze dry method has been tried. In the freeze dry process, Ba(NO₃)₂, ZrO(NO₃)₂ nH₂O, Y(NO₃)₃ nH₂O were chosen as low materials. The hydration numbers of ZrO(NO₃)₂ nH₂O and Y(NO₃)₃ nH₂O were measured by using a differential thermogravimetric analyzer. These nitrates were mixed to produce solution with the molar ratio of metal ions what we desired. The solution was atomized and frozen rapidly by using liquid nitrogen to avoid segregation. The frozen solution was dried under vacuum condition at temperature of about -40 ^oC. After finishing sublimation, obtained frozen powder was heated and synthesized at the temperatures of 600 to1000 ^oC. As a result of X-ray diffraction analysis and energy dispersive X-ray spectrometry, it is clarified that BaZr_1-xY_xO₃ can be synthesized at 800 ^oC which is lower more than 300 ^oC than conventional synthetic temperature. We are to report the possibility of reducing the sintering temperature of BaZr_1-xY_xO₃ by using obtained powders and properties of the sintered BaZr_1-xY_xO₃ such as the conductivity.