High-temperature proton conductors are promising electrolytes for protonic solid oxide fuel cells (H+-SOFCs). In this study, the relationship between the Zr doping content and structure, chemical stability, carbon dioxide resistivity, sinterability and electrochemical properties of BaZryCe0.8-yY0.2O3-delta (BZCYy), 0.0 <= y <= 0.8, are studied systemically using XRD, CO2-TPD, SEM. EIS and I-V polarization characterizations. Zr doping suppresses carbonate formation, CO2-TPD demonstrates that the formative rate of carbonate over BZCYy are 7.50 x 10(-6) and 8.70 x 10(-7) mol m(-2) min(-1) at y = 0.0 and 0.4, respectively. Investigation of sinterability shows that the anode-supported configuration helps the sintering of the thin-film electrolyte. Peak power densities of 220 and 84 mW cm(-2) are obtained at 750 and 450 degrees C, respectively, with BZCY0.4 electrolyte. Due to the favorable chemical stability against CO2 and good sintering in the thin-film configuration, BZCY0.4 is a potential electrolyte material for H+-SOFCs. (c) 2009 Elsevier B.V. All rights reserved.