Study on the properties of Al2O3-doped (ZrO2)0.92(Y2O3)0.08 electrolyte

Alumina (Al2O3) is doped into cubic structured yttrium stabilized zirconia (ZrO2)(0.92)(Y2O3)(0.08) (YSZ) by a ceramic method. The influence caused by the access of Al2O3 on the sintering behavior, mechanical and electrical properties of YSZ are studied, and the mechanism is analyzed. The experiments show that doping Al2O3 to YSZ can significantly improve the sintering behavior by reducing sintering temperature. Impedance analysis shows that the electrical properties can be also improved by doping Al2O3 because of the improvement of grain boundary conditions. YSZ doped with different amount of Al2O3 have different grain boundary conductivities among which the highest value belongs to the specimen of YSZ doped with 4 wt% Al2O3. Pure YSZ and YSZ doped with 4 wt% Al2O3 are used as the electrolytes to make SOFCs. The performance of SOFC with an Al2O3 doped electrolyte is better than that with a pure YSZ one. (C) 1999 Elsevier Science B.V. All rights reserved.