微波固相烧结制备La_(0.7)Sr_(0.3-x)Ca_xCo_(0.9)Fe_(0.1)O_(3-δ)阴极材料及性能表征  

Synthesis and Property Characterization of La_(0.7)Sr_(0.3-x)Ca_xCo_(0.9)Fe_(0.1)O_(3-δ) Powders by Microwave Sintering

作　　者：高文元[1] 孙俊才[1] 于洪浩[2] 

机构地区：[1]大连海事大学,辽宁大连116026 [2]大连轻工业学院,辽宁大连116034

出　　处：《稀有金属材料与工程》2005年第11期1738-1742,共5页Rare Metal Materials and Engineering

基　　金：国家'863'计划项目(2001AA515080);瑞典亚洲合作计划项目(DNR6964)

摘　　要：以碳酸盐和氧化物为原料,采用微波固相烧结法制备了La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ(简称:LSCCF,x=0.05,0.10,0.15和0.20)粉料.用XRD和SEM对LSCCF粉料的晶体结构和颗粒形貌进行了研究.结果表明:微波固相反应在1200℃下烧结0.5 h便可以形成密度为5.366 g/cm3,晶粒尺寸小于500 nm钙钛矿结构的粉料.而常规固相反应法在1300℃下烧结7 h只形成了密度为3.426 g/cm3,晶粒尺寸小于2000 nm钙钛矿结构的粉料.电导率测量结果表明:随着烧结温度的升高和Sr2+含量的增加,LSCCF样品的电导率变大,600℃～800℃范围内微波烧结制备的La0.7Sr0.15Ca0.15Co0.9Fe0.1O3-δ样品的电导率最小值为672 S/cm,且高于常规固相烧结制备的相同组成样品的电导率最小值425 S/cm.LSCCF粉料与Ce0.8Sm0.2O2电解质的混合物在800℃下烧结10 h后没有新相生成,表明LSCCF粉料与Ce0.8Sm0.2O2电解质具有良好的化学相容性.The powders of La0.7Sr1-xCaxCo0.9Fe0.1O3-δLa （LSCCF, x=0.05, 0.10, 0.15, 0.20） as a cathode materials for intermediate temperature solid oxide fuel cells were synthesized by using a microwave sintering method with carbonates and oxides. The crystal structure and the particle size and micrograph of LSCCF powders were investigated by XRD and SEM. The experimental results show that the powders which have single perovskite phase were prepared by microwave sintering method at 1200℃ for 0.5 h. Comparing with the powders sintered conventionally at 1300℃ for 7 h with a single perovskite phase in the density of 3.426 g/cm^3 and the particle size of 2000 nm, the microwave sintered powders have the density of 5.366 g/cm^3 and the particle size of smaller than 500 nm. The results also indicated that the electrical conductivity of the LSCCF sample increases with increasing sintered temperatures and the content of strontium. From 600℃ to 800℃, the minimum of electrical conductivity of La0.7Sr1-xCaxCo0.9Fe0.1O3-δ by microwave sintering method was 672 s/cm and it is higher than 425 S/cm of conventional sintering method. Heating the mixture of La0.7Sr1-xCaxCo0.9Fe0.1O3-δ and Ce0.8Sm0.2O2 at 800℃ for 10 h in air, no occur solid reaction and new phase between the two materials. So, LSCCF electrode material possesses good chemical compatibility with Ce0.8Sm0.2O2 electrolyte.

关 键 词：微波固相烧结 La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ 电导率 化学相容性 

分 类 号：TM911.4[电气工程—电力电子与电力传动]