V_2O_3系PTC陶瓷材料的研究进展  

Research Progress of V_2O_3-Based PTC Ceramics

作　　者：张兆刚[1,2] 陈敏[1] 李建军[1] 赵晨辰[1] 赵成明[1] 何向明[1] 

机构地区：[1]清华大学核能与新能源技术研究院,北京100084 [2]宜春学院江西省高等学校锂电新能源工程技术研究中心,江西宜春336000

出　　处：《稀有金属》2011年第4期581-586,共6页Chinese Journal of Rare Metals

基　　金：国家重大科学研究计划"973"项目(2011CB935902);国家自然基金(20901046)资助项目

摘　　要：PTC陶瓷材料是一种在基础科学和应用领域有着极为广泛用途的电子材料,可被用于自动调节加热器、温度传感器、保护和延时开关等工业产品。与其他PTC陶瓷材料相比,V2O3系PTC陶瓷材料在常态下有比较低的电导率和大的通流能力,其PTC效应来源于金属-绝缘体相变诱发的体效应,相变中没有晶体结构的变化,可用作过电流保护。通过改变掺杂浓度、温度、压力等因素,V2O3系PTC陶瓷材料会发生顺磁金属相和顺磁绝缘相的相变,这被认为是一个典型的由电子强关联作用引起的莫特转变,因此V2O3系PTC陶瓷材料可以为许多理论模型和实验手段提供一个检验平台。相对于其他PTC材料,V2O3系陶瓷材料的PTC效应来源于一种体效应,其PTC特性不受电压和频率的影响。由于相变过程中有电导的变化,可以作为导电材料来改善高温下锂离子电池的安全性能。简单介绍了PTC陶瓷材料的研究背景及分类,总结了V2O3系PTC陶瓷材料的产生机制、主要特点、影响因素和制备方法,并展望了V2O3系PTC陶瓷材料的应用前景及发展趋势。Ceramics with positive temperature coefficient（PTC） were a new class of materials in terms of fundamental and applied sciences,which could be used in a wide range of industrial applications such as self-regulating heaters,temperature sensors,and protective and time delay switching.Vanadium sesquioxide based ceramic had a very low electrical resistivity in its normal state compared with the other PTC materials.It utilized the bulk metal-insulator transition without any changes in crystal structure and enabled protection against high currents.The V2O3-based PTC ceramics was considered as the textbook example of a Mott transition induced by strong electron correlations,which occurred between a paramagnetic metallic（PM） and a paramagnetic insulator（PI） phase by changing doping level,temperature,or pressure.As such V2O3-based PTC ceramics served as a test bed for many theoretical models and a sustained experimental effort.Owing to its bulk switching phenomenon resulting to PTC effect,V2O3-based PTC ceramics had no the voltage and frequency dependence against the other PTC materials.The materials possessing conductance changes along with its phase transition were developed for use as conducting materials that could improve the safety performance of lithium batteries at elevated temperatures.The background of PTC effect in several kinds of ceramic materials was reviewed;the mechanism,performance,preparation and influencing factors of V2O3-based PTC ceramics were summarized.Moreover,the development of V2O3-based PTC ceramics was also prospected.

关 键 词：V2O3 PTC陶瓷材料 相变 掺杂 

分 类 号：TQ17[化学工程—硅酸盐工业]