掺杂对Ni-Mn-O系NTC热敏陶瓷及其电学性能的影响

EFFECT OF DOSAGE ON Ni-Mn-O DOPED NTC THERMO-SENSITIVE CERAMICS AND THEIR ELECTRICAL PROPERTIES

以Ni_(0.66)Mn_(2.34)O_4为负温度系数(negative temperature coefficient,NTC)的热敏陶瓷基体,分别掺入Mg^(2+)、Zn^(2+)、Al^(3+)、Fe^(3+)或Ni^(2+)等不同离子,以考察对结构和电性能的影响。X射线衍射结果表明:所有样品均为单相尖晶石结构,并计算出晶胞参数和近似的阳离子分布。电性能测量结果表明:当掺杂离子进入尖晶石结构B位时,对电阻率有较大影响;当掺杂离子进入尖晶石结构A位时,则对电阻率的影响较小。通过选择合适的掺杂离子可以调节其电性能参数。

Ni0.66Mn2.34O4 negative temperature coefficient（NTC） ceramics and its derivatives, doped by ions such as Mg^2＋, Zn^2＋, Al^3＋, Fe^3＋, and Ni^2＋, were prepared; the relationship between the structure and electrical properties of all NTC thermo-sensitive ceramics was investigated. X-ray diffraction shows that all samples have a single phase with a spinel structure. The lattice parameters and ap- proximate cation distribution were calculated. From the electrical properties measurement it could be inferred that when dopants occupy the B-site in the spinel structure, it has a strong effect on its resistivity, whereas, when dopants occupy the A-site, it has less effect. The electrical properties of NTC ceramics could be adjusted by controlling the metal ion dopants.