Tuning LSAF Perovskite Morphology by Synthesis Method

Öz

Lanthanum strontium aluminum ferrite (La0.8Sr0.2Al0.2Fe0.8O3±δ-LSAF) perovskites are drawing attention as cathodes in solid oxide fuel cells (SOFCs). The structural properties of these materials are mostly counting on the methods of preparation. In this study, two different preparation methods namely hydrothermal and sol-gel were applied to prepare LSAF perovskite. The characterization results including scanning electron microscopy (SEM), N2 adsorption-desorption, and Fourier transform infrared spectroscopy (FT-IR) are investigated in detail. The results showed that the preparation method played an important role on the microstructure of the LSAFs. It can be highlighted that the hydrothermal method is more successful in obtaining quite small nanoparticles.

Anahtar Kelimeler

• LSAF
• Hydrothermal Method
• Nanopowder
• Sol-gel Method

Sentez Yöntemi ile LSAF Perovskit Morfolojisinin Ayarlanması

Öz

Lantan stronsiyum alüminyum ferrit (La0.8Sr0.2Al0.2Fe0.8O3±δ-LSAF) perovskitleri, katı oksit yakıt hücrelerinde (KOYP) katot olarak dikkat çekmektedir. Bu malzemelerin yapısal özellikleri çoğunlukla hazırlama yöntemlerine dayanmaktadır. Bu çalışmada, LSAF perovskite hazırlamak için hidrotermal ve sol-jel olmak üzere iki farklı hazırlama yöntemi uygulanmıştır. Taramalı electron mikroskobu (SEM), N2 adsorpsiyon-desorpsiyon ve Fourier transform kızıl ötesi spektroskopisini (FT-IR) içeren karakterizasyon sonuçları detaylı olarak incelenmiştir. Sonuçlar, hazırlama yönteminin LSAF'lerin mikro yapısında önemli bir rol oynadığını göstermiştir. Oldukça küçük nano parçacıkların elde edilmesinde hidrotermal yöntemin daha başarılı olduğu görülmüştür.

Anahtar Kelimeler

• LSAF
• Hidrotermal Metot
• Nanotoz
• Sol-jel Metodu

Kaynakça

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