Synthesis and measurement of structural and magnetic properties of K-doped LaCoO_3 perovskite materials

作     者：Manjunath B.Bellakki C.Madhu Tobias Greindl Sandeep Kohli Patrick McCurdy V.Manivannan 

作者机构：Department of Mechanical EngineeringColorado State UniversityFort CollinsColoradoUSA Department of ChemistryColorado State UniversityFort CollinsColoradoUSA 

出 版 物：《Rare Metals》 (稀有金属（英文版）)

年 卷 期：2010年第29卷第5期

页      面：491-500页

核心收录：

学科分类：0808[工学-电气工程] 08[工学] 

主　　题：ceramic materials combustion synthesis X-ray diffraction magnetic properties structural properties 

摘      要：Polycrystalline La1-xKxCoO3 （0≤ x ≤ 0.2） rare earth cobaltates have been synthesized by a solution combustion method using glycine as a fuel. The synthesized ceramic materials were characterized by powder X-ray diffraction （XRD）, scanning electron microscopy （SEM）, Fourier transform infrared spectroscopy （FTIR）, and magnetic measurements and studied for physical properties, such as photoeatalytic activity. FTIR measurements in conjunction with XRD showed that phases beyond 10% K doping are accompanied by small amounts of impurities. Chemical titrations show the presence of Co^4＋ and account for the Co^3＋-Co^4＋ mixed-valency of the system. The parent LaCoO3 shows spin-glass transition at low temperatures, whereas doped samples show transition from spin-glass behavior to paramagnetic ordering on progressive doping of K. ＂Mixed-conductor＂ nature of these ceramics positions them as viable candidates for solid oxide fuel cell （SOFC） applications.