La_(0.7)Sr_(0.3-x)Ca_xCo_(0.9)Fe_(0.1)O_(3-δ)的柠檬酸盐法制备和性能

Preparation and Property Characterization of La_(0.7)Sr_(0.3-x)Ca_xCo_(0.9)Fe_(0.1)O_(3-δ) Powders by Citrate Method

采用柠檬酸盐法合成了La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ(LSCCF,x=0.05,0.1,0.15和0.2)粉料。TG-DSC分析表明,凝胶在320℃~558℃分解为相应的氧化物。XRD测试表明:产物前躯体在800℃下热处理3h就可制备出具有畸变钙钛矿结构的LSCCF粉料。电导率测试表明,随着烧结温度的升高和Sr2+含量的增加,样品电导率变大,其导电活化能变小。在600℃~800℃范围内,LSCCF样品的电导率为102S/cm^103S/cm,能够满足中温固体氧化物燃料电池阴极材料的要求。LSCCF粉料与Ce0.8Sm0.2O2电解质在800℃下烧结10h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 La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ（LSCCF, X = 0.05,0.1,0.15,0.2） were synthesized using a citrate method. Thermal analysis （TG-DSC）was used to characterize the thermal decomposition of the organic ligands of the gel. The gel decomposited its oxides at the range of 320℃ - 558℃. X- ray diffraction analysis indicated that a hexagonal perovskite phase was prepared at 800℃ for 3h in air. The measurement of the electrical conductivity indicated that the electrical conductivity of the LSCCF sample increases with increasing sintered temperature and the content of strontium. The activation energy of electrical conductivity decreases with the increasing electrical conductivity of the sample . From 600℃ to 800℃, the electrical conductivity of LSCCF was 10^2- 10^3 S/cm and it could satisfy the requirement of intermediate temperature SOFC. It was showed that La0.7Sr0.2Ca0.1Co0.9Fe0.1O3-δ and Ce0.8Sm0.2O2 did not make into a new phase at 800℃ for 10h in air. So, LSCCF possessed good chemical compatibility with Ce0.8Sm0.2O2.