Unraveling the defect chemistry and proton uptake of yttrium-doped barium zirconate

A review of the experimental literature documenting water uptake in yttrium-doped barium zirconate in combination with new results obtained here show that much of the observed scatter can be explained in terms of barium deficiency, which furthermore induces a lowering in cell volume. In addition, through a comparison of weight changes under regular and heavy water vapor pressure, strong evidence is found for bulk oxidation of the oxide by water simultaneous with hydration. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.