Solid-state Synthesis of La_0.7Sr_0.3MnO₃ Powders using Different Grinding Times

Abstract

Sr-doped lanthanum manganites (LSM) have been studied as promising materials for cathodes in solid oxide fuel cells (SOFC). In the present work La0.7Sr0.3MnO3 powders were synthesized by solid-state method evaluating the influence of dry or wet (using isopropanol) routes and different grinding times on the morphological and microstructural properties of LSM. The results of the synthesis of LSM powders pointed out that the use of solvent during homogenization results in poor crystallinity and only 6 hours of grinding at low speed in the ball mill is enough to obtain nano-sized crystalline phase by dry route. Scanning electron micrographs showed formation of agglomerates of fine primary particles. The electrical conductivity of the sintered LSM (La1-xSrxMnO3, x= 0.2, 0.3 and 0.4) pellets with about 35% of porosity was measured by the two probe technique, showing a slight increase in the conductivity with strontium content.

Colloidal Processing of Y0.08Zr0.92O2/La0.80Sr0.20MnO3 Semi-Cells Using a Sr-Doped Lanthanum Manganite Synthesized by a Citrate Route

“…Physical methods such as mechanosynthesis [11] and solid-state reactions [12] have been largely used for the synthesis of manganites, but in spite of the advantages of the lower cost of oxide precursors and simplicity, the physical methods require the use of high temperatures and long processing times and lead to some contamination the former and coarse particle size the last. Consequently, physical routes have been progressively replaced by wet chemical methods that make possible the synthesis of many different compositions, changing the relative ratio of the forming cations and allowing achieving high purity Materials 2021, 14, 7831 2 of 15 powders with a lower particle size in short processing times.…”