【摘要】 以Li₂CO₃,La₂O₃和ZrO₂为原料,分别添加Al₂O₃和Y₂O₃作为烧结助剂,制备锂离子固态电解质xAl₂O₃-Li₇La₃Zr₂O₁₂和xY₂O₃-Li₇La₃Zr₂O₁₂（分别简称为xAl₂O₃-LLZO和xY₂O₃-LLZO。x为摩尔分数,x=0,0.1,0.2,0.3,0.4和0.5）,研究Al₂O₃和Y₂O₃的添加量对LLZO的结构与锂离子电导率的影响。结果表明,在1 150℃烧结15 h时,Al₂O₃和Y₂O₃这2种烧结助剂都能稳定立方相石榴石结构LLZO。当Al₂O₃过量时,产生LaAlO₃杂相,当Y₂O₃过量时,产生Li₂ZrO₃和YO_1.458杂相。0.2Y₂O₃-LLZO在1100¹200℃范围内能形成稳定的立方相石榴石结构LLZO,并且在1 150℃烧结27 h不发生分解反应;LLZO的致密度和锂离子电导率都随烧结助剂含量增加而先增加后减小,Al₂O₃和Y₂O₃的最佳添加量x分别为0.2和0.3,所得0.2Al₂O₃-LLZO的致密度与离子电导率分别为94%和1.78×10^-4S/cm,0.3Y₂O₃-Li₇La₃Zr₂O₁₂的致密度与离子电导率分别为96%和5.23×10^-4S/cm。更多还原

【Abstract】 The garnet-type ceramic electrolyte Li₇La₃Zr₂O₁₂（LLZO） with composition of x Al₂O₃-Li₇La₃Zr₂O₁₂（x=0-0.4） and xY₂O₃-Li₇La₃Zr₂O₁₂（x=0, 0.1, 0.2, 0.3 and0.4） were synthesized by adding Al₂O₃ and Y₂O₃ as sintering aids and using Li₂CO₃, La₂O₃ and ZrO₂ as raw materials. The effects of the contents of sintering aids Al₂O₃ and Y₂O₃ on the lithium ion conductivity of solid lithium ion electrolyte LLZO were studied. The results reveal that two kinds of sintering aids both can stabilize the cubic phase of garnet structure LLZO after sintered at 1 500 ℃ for 15 h. The LaAlO₃ impurity phase is produced when Al₂O₃ is over added. The Li₂ZrO₃ and YO_1.458 impurity phases are produced when Y₂O₃ is over added. Among these samples,0.2 Y₂O₃-LLZO can stabilize the cubic phase from 1 100 ℃ to 1 200 ℃ and do not decompose when sintering at 1 150 ℃ for 27 h.The density of LLZO and the conductivity of lithium ion increase first and then decrease with increasing the content of sintering aids. The optimum additions of Al₂O₃ and Y₂O₃ are 0.2 and 0.3, respectively. The density and ionic conductivity of 0.2 Al₂O₃-LLZO are 94% and 1.78×10^-4S/cm, respectively. The density and ionic conductivity of 0.3Y₂O₃-Li₇La₃Zr₂O₁₂ are 96% and 5.23×10^-4S/cm, respectively.更多还原