稳定剂对Beta-Al2_O_3固体电解质性能影响

Influence of Stabilizers on the Performance of Beta-Al_2O_3 Solid Electrolytes

以Li2O、MgO和Li2O+MgO为稳定剂制备了beta-Al2O3固体电解质,并利用X射线衍射分析(XRD)、扫描电镜(SEM)和交流阻抗谱(EIS)等技术考察了稳定剂种类及含量对β"/β相的形成、显微结构和离子电导率的影响。研究表明,beta-Al2O3电解质中β"相的含量随稳定剂含量的增加而增加;但电解质的显微结构和离子导电性能随稳定剂的含量的增加呈现先优化后衰减,0.70%Li2O和3.80%(质量分数)MgO最佳。Li2O稳定剂对显微结构和离子导电性能的影响更为显著;MgO稳定剂能使β"/β相的合成温度低50℃;而Li2O+MgO稳定剂不易获得良好显微结构和离子导电性能的电解质材料。不同稳定剂作用的电解质的离子电导率由高到低依次为:Li2O>MgO>(Li2O+MgO)。

Beta-Al2O3 solid electrolytes with Li2 O,MgO and Li2O＋MgO as stabilizers were synthesized by a solid state reaction.The formation of β＂/β phase,microstructure and ionic conductivity of beta-Al2O3 was studied by XRD,SEM and EIS,respectively.The results show that the β＂ phase content increases with the increasing content of different additions,and the microstructure and ionic conductivity of the electrolytes are optimized first and then attenuated.The optimum synthesis condition is 0.70% Li2 O,or 3.80% MgO.Li2 O stabilizer has a more obvious effect on the microstructure and ionic conductivity of the electrolytes than MgO stabilizer.The forming temperature of β＂/β phase with MgO stabilizer is 50 oC lower than with Li2 O stabilizer,while Li2O＋MgO stabilizer has a negative effect on the properties of the electrolytes.The ionic conductivity of the electrolytes with different stabilizers decreases in the order of Li2OMgO（Li2O＋MgO）.