LISICON(锗酸锌锂)单晶的Li+离子电导

本文研究了Lisicon(锗酸锌锂)单晶的Li⁺离子电导率。发现各结晶学方向电导率之间的关系为σ_b≤σ_a≤σ_c≤σ_110],但各向异性不强。晶体中Li含量对电导率有明显的影响,当Li/Zn比率由6.7变到9.2时,300℃a方向电导率由4.3×10^-2Ω^-1·cm^-1增加到1.25×10^-1Ω^-1·cm^-1,logσT对1/T的曲线显示出三个转变点,分别在～80℃,～140℃和～300℃。电导的激活能分别为0.50—0.58eV(25—80℃),0.92eV(～80—140℃),0.64eV(～140—300℃)和0.36eV(>300℃),极化实验表明单晶的电子电导可以忽略。 关键词：

LITHIUM IONIC CONDUCTIVITY OF LISICON SINGLE CRYSTALS

Lithium ionic conductivity of LISICON single crystals grown by Czochralski method has been investigated. It was found that the conductivities in different orientations do not show strong anisotropy and the relations between them are: σ_b≤σ_a≤σ_c≤σ_110]. The lithium content in the crystals have obvious influence on conductivity. When Li/Zn ratio changes from 6.7 to 9.2, the conductivity in a-direction at 300℃ increases from 4.3 × 10^-2Ω^-1·cm^-1 to 1.25×10^-1Ω^-1·cm^-1. Three transition points at ～80℃, ～140℃ and ～300℃ have been shown in logσT vs. 1/T curves. The activation energy for conduction are 0.5-0.58 eV (25-80℃), 0.92 eV (80-140℃), 0.64 eV (140-300℃) and 0.36 eV (> 300℃) respectively. The polarization experiments indicated that LISICON is a lithium ionic conductor with negligible electronic conductivity.