NTC陶瓷材料Co_(1.5)Mn_(1.5-X)Ni_XO_4中阳离子分布与导电性间的关系

Correlation between Cation Distribution and Electrical Property in Co_(1.5)Mn_(1.5-X)Ni_XO_4 NTC Ceramic Material

本文通过溶胶-凝胶法制备三元系Co1.5Mn1.5-XNiXO4(X=0,0.1,0.3,0.5,0.7,1.0)NTC热敏电阻粉体材料,采用激光粒度分析、X射线衍射分析、红外光谱分析、电阻测量等手段,表征了煅烧材料的颗粒尺寸、烧结体的物相、红外吸收光谱以及陶瓷材料的电学特性。结合XRD、IR的分析结果,探讨了阳离子分布与热敏电阻电性能之间的关系,为解决热敏电阻材料高精度、高可靠性方面提供了依据。结果表明:随着Ni离子的增加,所得热敏材料的电阻率呈U型变化,材料常数B值从4427减小到2429K,该系列的电阻率、B25/50值调整范围较大,是一种具有实际应用价值的NTC热敏电阻。

The ternary system NTC （negative temperature coefficient） powders of Co1.5Mn1.5-XNiXO4 （X=0, 0.1, 0.3, 0.5, 0.7, 1.0） materials were prepared via sol-gel method. The particle size of calcined powders, phase structure, infrared absorption spectra and electrical properties were characterized by using laser particle size analyzer, XRD, IR and electrical measurements, respectively. Combined with the results of XRD and IR spectra, the relation between cation distribution and electrical properties of NTC thermistors were investigated, which provided evidence for high precision and reliability of NTC material. The results of electrical measurements indicated that the electrical resistivity display a U-shape curve with the increase of Ni content, whereas the thermal constant B25/50 decreased remarkably from 4 427 to 2 429 K. This means that electrical resistivity and B25/50 of Co1.5Mn1.5-XNiXO4 system could be adjusted to the desired values and then considered this ternary system as advanced semi-conducting materials for NTC thermistor applications.