The development of deep and low-temperature materials with excellent electrical properties is of great significance to deep space exploration and other fields.In this study,Ba/Fe co-doped LaCoO3 thermal sensitive ceramic material with negative temperature coefficient was prepared by traditional high temperature solid-state reaction method.The phase structure,microscopic morphology and ion valence distribution of the material were investigated by XRD,SEM,and XPS.The low-temperature electrical properties of LaCoO3 were tested in the range of 22-80 K and 80-290 K.The results show that the temperature range of the LaCoO3 material is reduced by co-doping modification.The ρ(22 K)is in the range of 1.85×105-6.94×106 Ω·cm,and the material constant B(22-100 K)is in the range of 146.09-162.75 K.In the deep and low-temperature environment,the conductive mechanism of the material changes from small polaron jump conduction above 80 K to double exchange conduction below 80 K,resulting in the abrupt change of the material constant B.The material system has potential application in the field of extreme low-temperature testing.
low temperature thermistor/NTC ceramics/electrical properties/La1-xBaxCo1-yFeyO3/transport mechanism/high temperature solid-state reaction method/conductive mechanism/low-temperature ion
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