Stability of $ {text{SrCe}}_{{0.9}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ and $ {text{SrZr}}_{{0.2}} {text{Ce}}_{{0.7}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ under H2 atmospheres

摘要

Previous H2 permeation tests showed a degradation of H2 permeation flux with time. To understand the cause of degradation and develop a solution, the stability of $ {text{SrCe}}_{{0.9}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ and $ {text{SrZr}}_{{0.2}} {text{Ce}}_{{0.7}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ samples were studied under dry and wet H2 atmospheres. Total conductivity of $ {text{SrCe}}_{{0.9}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ increased with time in dry H2. The X-ray diffraction pattern of $ {text{SrCe}}_{{0.9}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ after dry hydrogen atmosphere heat treatments show CeO2 peaks indicating that $ {text{SrCe}}_{{0.9}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ decomposes under dry H2 atmospheres; scanning electron microscopy and energy dispersive X-ray spectroscopy analyses prove that decomposition proceeded along the grain boundaries. $ {text{SrZr}}_{{0.2}} {text{Ce}}_{{0.7}} {text{Eu}}_{{0.1}} {text{O}}_{{3 - delta }} $ was investigated and demonstrated greater stability under dry hydrogen atmospheres. However, Zr substitution results in a tradeoff with electrical properties.