Sb掺杂对ZnO-V_2O_5多元系压敏电阻的影响

Effects of Antimony Dopants on the ZnO-V_2O_5 Multicomponent Varistor Ceramics

本文研究了V/Sb预合成粉、SbVO4和Sb2O3等三种不同形式的Sb掺杂对ZnO-V2O5基压敏陶瓷结构和性能的影响。化学计量比不变情况下,上述Sb掺杂方式的改变,使烧结过程中Sb3+离子在陶瓷样品中的浓度上升,促进Zn7Sb2O12型尖晶石相形成,材料晶粒随之细化。同时材料的压敏电压出现大幅上升,而非线性系数和漏电流密度受Sb掺杂形式的变化影响不大。Sb以V/Sb预合成粉进行掺杂可以获得较大尺寸的晶粒,有利于材料在低压方面的应用。

The microstructure and properties of three groups of multicomponent ZnO-V2O5 varistor ceramics were studied as a function of antimony dopant changing from the pre-synthesized V/Sb powder to SbV04 and then to Sb2O3. While remaining the stoichiometric ratios stable, the concentration of Sb^3＋ cation within the ceramic is increased with the antimony doping form variations. As a result, spinel formation in the ceramics was increased, while the average grain size of the ceramics was decrease accordingly. The breakdown voltages of the ceramic are increased dramatically, while other Ⅰ-Ⅴ characteristics, such as nonlinearity exponent and leak current density of the as studied ceramic remain rather constantly. The pre-synthesized V/Sb powder is the most effective antimony dopant in term of its effects on the grain growth of the ceramics. The ceramic is promising material in fabrication of low voltage chip varistor.