Effects of Fe2O3 doping on microstructural and electrical properties of ZnO-based linear resistance ceramics
ZnO-based linear resistance ceramics were synthesized from ZnO–MgO–Al2O3–La2O3–SiO2–Fe2O3 at 1320 °C for 3 h by the conventional ceramics method in air. The microstructure and the crystal characteristics were investigated by scanning electron microscope equipped with energy dispersive spectrometer and X-ray diffraction respectively. The influence of Fe2O3 content on the linear current–voltage (I–V) characteristic and dielectric characteristics have been systematically investigated in detail. The results indicated that the main phase of samples doped by Fe2O3 was hexagonal wurtzite structure of ZnO with the second phase of ZnAl2O4. The optimum result of linear I–V characteristic was obtained with nonlinear coefficient of 1.08, when the content of Fe2O3 was 0.50 mol%. With the increasing of dopant Fe2O3 contents, the dielectric constant and resistivity of ZnO-based linear resistance ceramics were influenced significantly, moreover, the resistance–temperature characteristics presented the negative temperature coefficient effects.
KeywordsFe2O3 Nonlinear Coefficient Fe2O3 Content ZnAl2O4 Varistor Ceramic
This work was supported by the Key Project of Chinese Ministry of Education (No. 210218), Scientific and technological project of Wenzhou (H20100079, H20100087), and the Graduate Innovation Fund of Shaanxi University of Science and Technology.
- 10.M. Matbuaka, Nonohmic properties of zinc oxide ceramics. Appl. Phys. 10(6), 736–746 (1971)Google Scholar
- 12.Z.Y. Lu, Y.Y. Cai, Z.W. Chen et al., Effects of Fe impurity on performance of ZnO varistors. Rare Metal. Mater. Eng. 36, 187–190 (2007)Google Scholar
- 24.W. Heywang, Resistivity anomaly in doped barium titanate. J. Am. Ceram. Soc. 10(47), 488–490 (1996)Google Scholar