OH− ion transport in hydrated layered perovskite LaSr3Fe3O8(OH)2∙xH2O in the middle temperature range

Influences of Hydration‐Dehydration on Local Structure in Layered Perovskite LaSr3Fe3O10

“…The evaporation of H 2 O from hydrated LSF affects these results. An earlier TG investigation found that heating up to 100 °C eliminates the H 2 O [10,11] . The above‐mentioned rock‐salt interlayer distance corresponds to the La1‐O3_1 bond length, whereas the La1‐O3_2 bond length concerns the ab plane near the rock‐salt interlayer (Figure 1).…”

“…When temperatures exceed 300 °C, the Sr1‐O3_1 bond length in hydrated LSF is quite close to that of regular LSF. The earlier studies of thermogravimetry (TG) reported that the heating hydrated LSF up to 100 °C evaporated the intercalated H 2 O molecules and the heating hydrated LSF up to 300 °C desorbed the introduced OH − ions [10,11] . Thus, the OH − desorption decreases the Sr1‐O3_1 bond length by heating hydrated LSF up to 300 °C.…”

“…Using the electromotive force (EMF) approach, we previously discovered that the hydrated LSF also demonstrated ion conduction in the middle-temperature range of 120 °C-200 °C. [11] The results propose that the hydrated LSF is possibly applicable to electrodes or electrolytes for the middle range temperature operating fuel cells. The EMF of hydrated LSF investigated at 150 °C showed the lowest negative value under the high vapor partial pressure gradient, which is an evidence of OH À ion conduction.…”

“…From the results, we expect that the hydrated LSF shows ion conductivity in the middle‐temperature range as well. Using the electromotive force (EMF) approach, we previously discovered that the hydrated LSF also demonstrated ion conduction in the middle‐temperature range of 120 °C–200 °C [11] . The results propose that the hydrated LSF is possibly applicable to electrodes or electrolytes for the middle range temperature operating fuel cells.…”

“…The earlier studies of thermogravimetry (TG) reported that the heating hydrated LSF up to 100 °C evaporated the intercalated H 2 O molecules and the heating hydrated LSF up to 300 °C desorbed the introduced OH À ions. [10,11] Thus, the OH À desorption decreases the Sr1-O3_ 1 bond length by heating hydrated LSF up to 300 °C. From these results, hydrated LSF keeps the large Sr1-O3_1 bond length unless desorbing OH À ions.…”