Electrical properties of BaFe0.9Sn0.1O3–BaCo0.02ⅡCo0.04ⅢBi0.94O3 composite thick-film thermistors

作者：Chang-Lai Yuan; Ying Luo; Qin Feng; Yun Yang; Xiu-Juan Zhou; Xin-Yu Liu

来源：Rare Metals, 2020, 39(11): 1321-1327.

The BaFe0.9Sn0.1O3-BaCo0.02ⅡCo0.04ⅢBi0.94O3 composite thick films were prepared by screen printing.X-ray diffraction(XRD) analysis confirms that the composite films are still composed of BaCo0.02ⅡCo0.04ⅢBi0.9403 and BaFe0.9Sn0.1O3 phases.For the prepared B aFe0.9Sn(0.1 O3-B aCo0.02ⅡCo0.04ⅢBi0.94O3 composite thick films,a linear relationship between the logarithmic resistivity and the reciprocal of the absolute temperature is observed,indicating an excellent NTC thermistor characteristic.The values of resistivity at 25℃,thermistor constant and activation energy,decreasing with B aCo0.02ⅠCo0.04ⅢBi0.94O3 content increasing,are in the range of 8.9-92,990Ω·cm,1,126-3,777 K and 0.097-0.325 eV,respectively.Impedance analysis shows that at higher BaCo0.02ⅡCo0.04ⅢBi0.94O3 content,the electrical properties of the composite films are mainly attributed to the contribution of grains and grain boundaries.With the gradual decrease of BaCo0.02Ⅱ-Co0.04ⅢBi0.94O3 content,the grain boundaries affect strongly the electrical properties of the composite films.