Na_(5+x)YAI_xSi_(4-x)O_2快离子导体的导电机理

Na_(5+x)YAl_xSi_(4-x)O_(12)(NYAS)快离子导体中的铝、钇、硅、氧及部分钠离子堆积组成了独特的刚性结构,使之在其环与环之间、柱与柱之间形成了传导通道。另一部分钠离子很容易在通道中迂移传导,因而这类离子导体具有很高的离子电导率。本文从传导机理出发,计算了NYAS中的载流子浓度值,其结果与实验值接近,并从传导机理及简单跳跃模型出发,推出了NYAS中的离子电导率与组成X的变化趋势,获得了与实验结果完全吻合的结论。     

磷硼酸盐非晶态锂离子导体的红外和拉曼光谱研究

Li_2O—B_2O_3—P_2O_5系统非晶态的电导率、氧离子体积、Tg等在B_2O_3/P_2O_5约等于1时存在极值或急剧变化的Mixed Anion Effect,采用红外光谱、拉曼光谱研究了非晶态的微观结构,从理论上解释了现象产生的原因。     

锂离子电池阴极材料Li1＋Mn2O4的合成与特性

对Ｌｉ１＋ｘＭｎ２ｏ４的合成性能进行了初步的探索。原材料有采用分析纯Ｌｉ２ＣＯ３和电解二氧化锰，对原材料ＭｎＯ２进行热处理，使之成为ε相并排除结晶水。     

STUDY ON SYNTHESIS PROPERTIES STRUCTURES AND APPLICATIONS OF CERAMIC SEMICONDUCTOR COOLING MATERIALS (CFCC)

Pseudoternary system (Bi_2Te_3-Sb_2Te_3-Sb_2Se_3) ceramic smeiconductor cooling materials were pre-pared in solid state reaction with conventional techniques ofsintering ceramics.The effect of doping on the properties ofthe material was studied.X-ray diffraction analysis showedthat n-p-type materials were solid solutions based on Bi_2Te_3and Sb_2Te_3 respectively.SEM photographs proved that theboth types of materials were inhomogeneous and layer struc-ture.The values of fingure of merit for n-type and p-typematerials were 3.4×10~(-3) K~(-1),respectively.The fabricatedthermoelectric modlules made of the materials provided excel-lent cooling effect.     

复相导电型红外辐射陶瓷中TiC对堇青石结构影响的研究

在高温炉内还原气氛下根据固相化学反应理论制备出了碳化钛—堇青石导电红外陶瓷材料,材料电导率为1×10~(-1)～2×10~(-4)s/cm,红外辐射率ε为86％,用XRD红外光谱等现代测试手段对样品进行了结构分析,研究表明体系中堇青石结构随TiC配比不同而发生变化,且这种变化带来了辐射性能较单相有了很大的改善。     

STUDY ON THE STRUCTURE AND PROPERTIES OF SEMICONDUCTOR CERAMIC COOLING MATERIALS

In this paper,thermoelectric polycrystalceramic materials were prepared by a new ce-ramic technology.The p-type 72% Sb_2Te_3+25%Bi_2Te_3+3%Sb_2Se_3 doped with Te and90%Bi_2Te_3+5%Sb_2Te_3+5%Sb_2/Se_3 dopedwith SbI_3 or Agl samples were studied.Thenew ceramic cooling materials have an inhomo-geneous structure,higher mechanical strengthand the thermoelectric properties.With the helpof phase diagrams,Differantial Thermal Anal-ysis,X-Ray diffractograms,the observationof high temperature microscope and the relationbetween technology conditions and thermoelectricproperties were obtained in optimum technologyconditions.Measurements of properties showthat the sintering temperature and time have aneffect on the thermoelectric properties of thesamples.Scan electronic microscope shows thatthe polycrystal ceramic materical has an obviouslayered structure.Electrical probe microscopeanalysis indicates that the mol contents of Bi,Te,Sb and Se which compose samples are re- spectively comsistent with original compositio     

Li_2O-B_2O_3-ZrO_2系统玻璃的结构研究

用径向分布函数和红外光谱分析方法研究了Li_2O-B_2O_3-ZrO_2和Li_2O-B_2O_3等系统玻璃的结构。得出了Li_2O-B_2O_3-Z_rO_2系统玻璃中的Zr~(4+)离子影响碱硼酸盐玻璃的网络结构。随着Z O_2含量的增加BO_3三角体转变为BO_4四面体,并形成含BO_4四面体较多的硼酸盐基团。在含Z O_2为10mol％的锂硼酸盐玻璃的RDF曲线中,第一峰的位置r_1=1.54A可能是~3B-φ(φ表示桥氧),~4B-φ和Z_r-O原子对距离的贡献;第二峰的位置r_2=2.28A是O—O;Li O和Z_r-O原子对距离的贡献;第三峰的位置r_3=3.30A是Zr-Z_r原子对距离。玻璃中的Z_r~(4+)离子作为网络修饰体以6配位状态填充于硼酸盐基因空隙中。     

Li_2O-P_2O_5-V_2O_5系统玻璃“晶化前期”电导研究及ESR对钒离子价态分析

本文确定了Li_2O-P_2O_5-V_2O_5系统玻璃的形成范围。采用交流电桥法测定了几组样品的电导率,lg(σT)～1/T曲线表明是由两个直线段构成,电导率在转变温以后的“晶化前期”异常增加,分析认为由于玻璃结构有序化程度增加所致。利用ESR实验对玻璃中钒离子价态进行了分析,表明该系统玻璃仅以V~(4+)和V~(5+)钒离子状态存在。随Li_2O含量增加,V~(5+)离子浓度增加,试样电子电导下降。文中从结构角度对玻璃性能进行了讨论。     

PZT压电陶瓷的微观结构研究及能带计算

用固相反应烧结法制备了纯相ＰＺＴ及掺Ｌａ＾３＋、Ｎｂ＾５＋的ＰＺＴ压电陶瓷片，利用计算机程序ＰＯＷＤ１２模拟出了样品的空间位置，从理论上说明了样品在居里点以下具有压电性能。用ＸＰＳ现代测试手段分析了样品中电子的分布情况。根据固体物理中的能带论，用量子化学方法计算了ＰＺＴ压电陶瓷的带结构，理论计算与ＸＰＳ测试吻合较好。