Academic Journal of Materials & Chemistry, 2023, 4(2); doi: 10.25236/AJMC.2023.040205.
Sichuan University, Chengdu, Sichuan, 610042, China
The CaCu3Ti4O12 ceramics have been successfully prepared by the sol-gel method. We have set four different temperature gradients (950℃, 1000℃, 1050℃, 1100℃) as the sintering temperatures for CaCu3Ti4O12 ceramics to study the influence of different temperatures on the thermistor. The effects of different sintering temperatures on the structure of CaCu3Ti4O12 ceramics were analyzed by X-ray diffraction (XRD). Scanning electron microscope (SEM) images demonstrate that the grain size of ceramic samples will increase with the increase of the sintering temperature. X-rayphotoelectron spectroscopy (XPS) has been used to study the chemical states on the surface of ceramic samples. It is confirmed that the coexistence of Cu+/Cu2+ and Ti3+/Ti4+ is the cause of the conductivity of CaCu3Ti4O12 ceramics. All ceramic samples have NTC behavior, room temperature resistivity (ρ25), material constant (B) and the relationship between the nature logarithm of the resistivity and the temperature has been studied in this paper.
CCTO Ceramic; Temperature gradients; Sintering; Temperature sensor
Wei Chen. Influence of the preparation conditions on the electrical properties with negative temperature coefficient. Academic Journal of Materials & Chemistry (2023) Vol. 4, Issue 2: 26-30. https://doi.org/10.25236/AJMC.2023.040205.
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