Evaluation of stability and functionality of BaCe1-xInxO3-delta electrolyte in a wider range of indium concentration

Abstract

The properties of BaCe1-xInxO3-delta (x = 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, and 0.40) as proton conducting electrolyte are examined. The dense electrolyte is formed after sintering at 1300 degrees C for 5 h in air. The samples with In content > 25 mol% contain In2O3 as a secondary phase. The highest total conductivity is around 5x10(-3) S/cm for BaCe0.75In0.25O3-delta in the wet hydrogen atmosphere at 700 degrees C. After exposure to pure CO2 atmosphere at 700 degrees C for 5 h, the concentrations of at least 15 mol% In can completely suppress degradation of the electrolyte. The power density of Ni-BaCe0.75In0.25O3-delta/BaCe0.75In0.25O3-delta/LSCF-BaCe0.75In0.25O3-delta fuel cell tested in wet hydrogen atmosphere reaches 264 mW/cm(2) at 700 degrees C. This result is an indication of stability and functionality of this electrolyte and its versatility in respect to type of fuel and performing environment.