摘要
采用甘氨酸-硝酸盐(GNP)法合成出La0.6Sr0.4Fe0.8Co0.2O3超细粉体,探讨各因素对产物的晶体结构和显微形貌的影响,研究烧成温度对电导率的影响.研究表明,G/Mn+控制在2.0—3.0、热处理温度为750℃是最佳的合成条件,1200℃烧成样品具有最优良的电性能.在室温～900℃温度范围内,样品的电导率在600℃附近出现最大值,低温段的导电行为符合小极化子导电机制.与常规固相法相比,GNP法制备样品具有更好的烧结活性和导电性能.
La0.6Sr0.4Fe0.8Co0.2O3 oxides powders of perovskite-type were synthesized by the low temperature Glycine-Nitrate Process(GNP). The contributing factors to the crystal structure and morphology of synthesized powders were examined, and the desired synthesis conditions were studied. The influences of sintering temperature on the electrical conductivities were studied, indicating that the sample sintered at 1200degreesC showed highest electrical conductivity. In the range of room temperature to 900degreesC, the electrical conductivities of the samples sintered at different temperatures respectively increase with temperature to the maximums near 600degreesC and then decrease. It was verified that the hopping of small polaron is the dominating mechanism of the electrical conduction at low temperatures. The samples sintered at different temperatures have similar activation energies of 0.103similar to0.122eV. Compared with the La0.6Sr0.4Fe0.8Co0.2O3 synthesized by the conventional solid state reaction method, those synthesized by GNP exhibit better sintering activity and electrical conductivities.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2003年第5期1039-1044,共6页
Journal of Inorganic Materials
基金
湖北省自然科学基金(2001ABBO075)
武汉市晨光计划项目(20015005031)
材料复合新技术国家重点实验室基金
