Ba掺杂SrTiO_3SOFC阳极材料的制备与电性能分析

Preparation and Electrical Properties of Ba-doped SrTiO_3 as Anode Materials for SOFC

采用高温固相法合成BaxSr1-xTiO3-δ(x=0.1～0.3,摩尔分数)粉体,制备固体氧化物燃料电池(solid oxide fuel cell,SOFC)阳极材料,并对材料进行X射线衍射、扫描电子显微镜分析及相对致密度、高温电导的测量。Ba的掺入增大材料的晶胞参数,但是阻碍材料的致密化,材料的电子电导率和离子电导率都随Ba掺量的增加而提高,900℃时,Ba0.3Sr0.7TiO3-δ离子电导率为5.81×10-3 S/cm。Ba0.3Sr0.7TiO3-δ是一类较好的燃料电池阳极掺杂母体材料。从缺陷化学和晶体几何结构的角度分析掺杂元素Ba的作用机理。

BaxSr1-xTiO3-δ（x=0.1-0.3,mole fraction） powders used for anode materials of solid oxide fuel cells（SOFCs） were synthe-sized via the conventional solid-state reaction.Structure and properties of Ba-doped SrTiO3 were evaluated by the X-ray diffraction,scanning electron microscopy,density determination,electrical and ionic conductivity measurement.With increasing barium amount,lattice parameter of BaxSr1-xTiO3-δ increases and relative density decreases.Ba-doping enhances both electrical and ionic conductivi-ties.The ionic conductivity of Ba0.3Sr0.7TiO3-δ is 5.81 × 10-3 S/cm at 900 ℃.Ba0.3Sr0.7TiO3-δ is a good host material for the SOFC anodes.The doping mechanism of Ba in Ba0.3Sr0.7TiO3-δ is discussed with respect to the defect chemistry and lattice geometric structure.