ZnO-doped BaZr0.85Y0.15O3-delta perovskite oxide sintered at 1500 degrees C has bulk conductivity of the order of 10(-2) Scm(-1) above 650 degrees C, which makes it an attractive proton-conducting electrolyte for intermediate-temperature solid oxide fuel cells. The structure, morphology and electrical conductivity of the electrolyte vary with sintering temperature. Optimal electrochemical performance is achieved when the sintering temperature is about 1500 degrees C. Cathode-supported elecrolyte assemblies were prepared using spin coating technique. Thin film electrolytes were shown to be dense using SEM and EDX analyses. (C) 2009 Elsevier B.V. All rights reserved.