We have examined the oxygen relaxation and oxide ion conduction in yttria stabilized cubic zirconia, and the influence of the doped ceria content. Two maxima of the internal friction (IF) were observed for some CeO2 doped cubic Zr0.8−xCexY0.2O1.9 ceramics in the temperature range of 25~420 and at 9Hz using forced torsion method. The ceria addition reduced the amplitude of IF and the oxide ion conduction of Zr0.8−xCexY0.2O1.9. The result indicated that the doped CeO2 reduced the mobility of oxygen in yttria stabilized cubic zirconia even with the same concentration of defects.
The solid state reaction at the interface between ZrO 2 electrolyte and CeO 2 interlayer in a model solid oxide fuel cell (SOFC) was examined. At the interface, both Y 2 O 3 -stabilized ZrO 2 electrolyte and CeO 2 diffuse each other and form the ZrO 2 -CeO 2 solid solution. Cation diffusion coefficient and enthalpy were derived by using the Y 2 O 3 -doped ZrO 2 /CeO 2 diffusion couples at 1400-1600°C. The data of inter-diffusion enthalpy of Zr and Ce was 510 kJ mol −1 which should enable to predict how much the interface solid state reaction occurs for simulating the long time cell operation.
We observed the solid state reaction at the interface between ZrO2 electrolyte and CeOx interlayer in a model SOFC. At that interface, ZrOx and CeOx diffuse each other and the Zr-CeO solid solution lowers the cell performance. In this report, diffusion coefficient which enables to predict how much the reaction occurs is derived by using the ZrO2 / CeOx diffusion couples, simulating the long time operation. Stabilized ZrO2 powder and Gd-added CeO2 powder were laminated into two layers and pressed. To measure more practical interface, we chose the material powders used for cell production. Then the pressed powder was sintered at tempertures of 1350 to 1600 oC for 24 hours. The sintered blocks were cut into 3mm thick samples and polished. The ZrOx / CeOx interface were observed by scanning electron microscope (SEM) and analyzed about composition and their amount by Energy-dispersive X-ray spectroscopy (EDS).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.