硅掺杂石榴石型Li_(7)La_(3)Zr_(2)O_(12)固体电解质的制备及性能表征  

Preparationand Characterization of Silicon-doped Garnet Li_(7)La_(3)Zr_(2)O_(12)Solid Electrolyte

作　　者：黄晓东 王庆伟[1] 刘萌 金广辉 Huang Xiaodong;Wang Qingwei;Liu Meng;Jin Guanghui(School of Material science and Engineering,Henan University of Technology,Zhengzhou 450001,China)

机构地区：[1]河南工业大学材料科学与工程学院,河南郑州450001

出　　处：《中国稀土学报》2024年第3期503-508,共6页Journal of the Chinese Society of Rare Earths

基　　金：河南省高等学校重点科研项目计划项目(21A430009)资助。

摘　　要：石榴石型固体电解质Li_(7)La_(3)Zr_(2)O_(12)(LLZO)因为具有高的锂离子电导率、宽的化学窗口和良好的锂金属稳定性而被广泛研究。为进一步提高其电化学性能,得到稳定立方相结构,本文采用高温固相法制备出Si掺杂LLZO(Li_(7)La_(3)Zr_(2-x)Si_(x)O_(12))固体电解质。探究了Si掺杂量x对烧结陶瓷片的物相组成、晶体结构、微观形貌、相对密度、锂离子电导率和电导活化能的影响。结果表明,随着Si掺杂量x的增加,Li_(7)La_(3)Zr_(2-x)Si_(x)O_(12)烧结陶瓷片的气孔减少,相对密度增加,锂离子电导率随着Si掺杂量x的增加呈现出先上升后下降的趋势。当Si掺杂量x=0.24时,Li_(7)La_(3)Zr_(2-x)Si_(x)O_(12)烧结陶瓷片的锂离子电导率达到了最大值4.86×10^(-4)S·cm^(-1),电导活化能达到了最低值为0.32 eV。Garnet solid electrolyte Li_(7)La_(3)Zr_2O_(12)(LLZO)has been widely studied because of its high lithium ion conductivity,wide chemical window and good lithium metal stability.In order to further improve its electrochemical performance and obtain a stablecubic phase structure,Si-doped LLZO(Li_(7)La_(3)Zr_(2-x)Si_(x)O_(12))solid electrolytes were prepared by high temperature solid state method.The effects of Si doping amount x on the phase composition,crystal structure,micro-morphology,relative density,lithium ionic conductivity and conductance activation energy of sintered ceramic sheets were investigated.The results show that with the increase of Si doping content x,the porosity of Li_(7)La_(3)Zr_(2-x)Si_(x)O_(12)sintered ceramics decreases,the relative density increases and the lithium ion conductivity increases at first and then decreases with the increase of Si doping content x.When the Si doping content is 0.24,the lithium ion conductivity of Li_(7)La_(3)Zr_(2-x)Si_(x)O_(12)sintered ceramic sheet reaches the maximum value of 4.86×10^(-4)S·cm^(-1)and the conductance activation energy reaches the lowest value of 0.32 eV.

关 键 词：固体电解质 Li_(7)La_(3)Zr_(2)O_(12) 锂离子电导率 Si掺杂 

分 类 号：TM911[电气工程—电力电子与电力传动]