【作者】 陈红萍；

【导师】 武七德； 赵修建；

【作者基本信息】 武汉理工大学 ， 建筑材料与工程， 2012， 博士

【摘要】 无机固态电解质由于具有特殊的性能和潜在的应用前景,近年来引起广大研究者的关注,研发室温高离子导电性无机固态电解质是其重要发展方向。本论文对NASICON型以LiTi2(PO4)3为基的玻璃陶瓷及其薄膜电解质的制备与性能进行了系统研究,主要研究结论和创新点如下：1. Li2O-Al2O3-TiO2-P2O5(LATP)玻璃室温电导率极低,经热处理后形成玻璃陶瓷,其电导率显著增加；在1000℃晶化获得的玻璃陶瓷,室温离子电导率达到8.6×10-4S·cm-1。2.引入Si02能有效提高玻璃形成能力,其△T(Ti-Tg)值和Hruby玻璃形成能力指数值分别由29.9℃和0.04提高到61.8℃和0.14。但同时导致玻璃晶化时产生多种杂质相,由于阻塞效应导致离子电导率降低,所得玻璃陶瓷的最高离子电导率仅为4.1×10-4S·cm-1。3.适量引入B203可改善玻璃形成能力,晶化方式从一维生长模式转变为二维生长模式,析晶活化能降低,晶化指数升高。B203的引入促进主晶相LiTi2(PO4)3的析晶,抑制杂质相生长,可明显提高导电性能,当晶化温度为900℃时室温电导率高达1.3×10-3S.cm-1。晶化温度高于1000℃时AIPO4和Ti02含量增加,阻塞效应与空间电荷效应共同作用使得其Arrhenius曲线图呈现非线性变化。4.在LATP玻璃中掺入少量La203可提高其玻璃形成能力,但促进了玻璃中AlPO4和TiO2及未知相的析晶,导致离子电导率下降,最佳晶化温度900℃时离子电导率为5.85×10-4S·cm-1。5.采用离子电导率为6.6×10-5S·cm-1的Li1.3Al0.31.7PO43陶瓷靶材,用射频溅射法制备了LATP非晶态薄膜,溅射功率为100W,氧分压为20%时,随着基片温度升高薄膜更加致密,电导率从0.34x10-SS·cm-1增加到2.46×10-5S·cm-1。基片温度高于400℃时,薄膜与ITO玻璃基板发生反应,使得导电性能变差。更多还原

【Abstract】 Due to its special properties and potential applications, more and more researchers pay attentions to inorganic solid eylectrolyte in recent years. It is the main research direction for solid-state electrolyte to develop inorganic solid electrolytes with high ionic conductivity at room temperature. The preparation and properties of the glass-ceramics and thin films based on LiTi2(PO4)3with NASICON-analogy structure were studied systematicly in this dissertation. The main conclusions are as follows:1. The Li2O-Al2O3-TiO2-P2O5(LATP) glass is poor in ionic conduction, while the conductivity of glass-ceramics prepared by heat treatment increased significantly. The glass-ceramic obtained by heattreated at1000℃of LATP glass shows the total conductivity at25℃coming up to8.6×10-4·cm-1..2. The introduction of SiO2improved glass forming ability, the value of ΔT(Ti-Tg) and KH(Hruby factor) rose from29.9℃and0.04to61.8℃and0.14, respectively. But the glass-ceramic contains much impurity phases, lead to lower ionic conductivity. The ionic conductiviy of glass-ceramic at room temperature comes up to4.1×10-4S·cm-1.3. The introduction of appropriated amount of B2O3results also in the increased glass forming tendency. The activation energy for crystallization reduced and the mode of crystal growth changed from one-dimensional to two dimensional growth. The boron addition promots the precipitation of the main crystalline phase LiTi2(PO4)3, restrains the precipitation of second phase, accordingly greatly enhances the conductive properties. The largest ionic conductivity of glass-ceramic (1.3×10-3·cm-1) at25℃was obtained by crystallization of the boron-incorporated glass sheet at900℃. When the heattreating temperature raise to1000℃, the content of unexpected dielectric phases (TiO2, AIPO4) increased, the synergy effects of blocking and space-charge induce the Arrhenius plots exhibiting nonlinear variation.4. La incorporation in LATP could also improve the glass-forming ability; yet La2O3acts as a nucleating agent and promotes the crystallization of AIPO4, TiO2and unknown phases, resulting in the decline of the ionic conductivity.5. LATP amorphous thin films were fabricated at various substrates temperatures from25to400℃by RF magnetron sputtering method using Li1.3Al0.3Ti1.7(PO4)3ceramic target. When the sputtering power is100W and partial pressure of oxygen is20%, with increasing substrate temperature, the thin film structure become denser, smoother and more uniform, the ionic conductivity enhances gradually from0.34×10-5S·cm-1to2.46×10-5S-cm-1. When the substrate temperature is higher than400℃, the reaction between the thin film and ITO glass substrate degrades the conductive performance of thin films.更多还原