Solid Oxide Fuel Cells: Strontium-Doped Lanthanum Manganite Obtained by the Citrate Technique

摘要

Nowadays, the La_(1-x)Sr_xMnO_3 (LSM) is one of the most common cathodic materials used in the solid oxide fuel cells (SOFCs). The dopant strontium increases the electronic conductivity of the material, besides presents an excellent electrochemical performance, relatively good chemical and thermal stability and compatibility with solid electrolyte of ZrO_2/Y_2O_3 (YSZ). In this work, a contribution to the study of synthesis of LSM is presented with strontium concentration of 50 mol % by the citrate technique. The powders have been characterized for various techniques, as gas absorption and adsorption, X-ray fluorescence spectroscopy, laser scattering granulometry, gas helium picnometry, scanning electron microscopy (SEM), X-ray diffractometry (XRD) and calculations of theoretical density and particle average diameter. The ceramics have been characterized by SEM and XRD. The adequate characteristics of LSM have been evaluated aiming at the use in the preparation of suspensions for cathodic thin films of SOFCs.