Influences of Hydration‐Dehydration on Local Structure in Layered Perovskite LaSr 3 Fe 3 O 10

Abstract The layered perovskite LaSr 3 Fe 3 O 10 (LSF) easily hydrates under ambient air. The hydrated LSF transports hydroxides in the middle‐temperature range of 100 °C–250 °C. This study used X‐ray absorption fine structure analysis on normal and hydrated LSF from room temperature to 350 °C to evaluate the relationship between local structures and ion transport characteristics. The H 2 O molecules are mainly intercalated into rock‐salt interlayers, which are close to the La1 and O3 sites. The generated OH − ions are found at O3 sites, which are closer to Sr ions than La ions. The intercalated H 2 O molecules and formed OH − ions expand the spaces of the rock‐salt interlayers. The temperature dependence of the local crystal structure was also studied in this study. According to the findings, the presence of OH − ions on the O3 sites, which are closer to Sr ions, plays a significant role in OH − transport in the medium temperature range.