Preparation of Mesoporous La_(0.8)Sr_(0.2)MnO_3 Infiltrated Coatings in Porous SOFC Cathodes Using Evaporation-Induced Self-Assembly Methods

摘要

We used evaporation-induced self-assembly (EISA) methods to infiltrate solid oxide fuel cell cathodes with La_(0.8)Sr_(0.2)MnO_3. A single infiltration step using an EISA solution was found to generate thin catalyst coatings through the entire thicknesses of 75 - 750 μm thick porous media, including Y2O_3 stabilized ZrO_2 (YSZ), La_(0.8)Sr_(0.2)MnO_3 (LSM), and La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_3 (LSCF). After multiple infiltration and calcination steps, the LSM particles in LSCF cathodes of commercial button cells coated the pores as thin layers through the thickness with a slight increase in the concentration at the functional layer near the electrolyte / cathode boundary. The infiltrated La_(0.8)Sr_(0.2)MnO_3 coatings were examined using transmission electron microscope (TEM) and were shown to be mesoporous, indicating that the nanostructure of electrocatalytic coatings can be tailored using this approach.