BaTiO3与CaCu3Ti4O12的介电性能比较

分别采用溶胶-凝胶法和固相反应法制备BaTiO3纳米粉体和CaCu3Ti4O12多晶块材,并系统地研究两者的介电性能。实验结果表明:BaTiO3体相陶瓷的介电性能受温度的影响较大,当频率在200~150 000 Hz范围内变动时,其室温介电常数ε最高达2 967,具有很好的频率稳定性、介电损耗小,可用来制作某些电子元件;然而CaCu3Ti4O12多晶块材的介电常数ε在(1 kHz,300 K)时高达14 000,并在100~350 K的温区内基本保持恒定,具有极好的温度稳定性。因此,在现实的应用过程中,CaCu3Ti4O12多晶块材以高介电常数、受温度影响变化小、介电损耗小等优点而更具应用前景。

Comparison of Dielectric Property between BaTiO3 and CaCu3Ti4O12

Nano- powder BaTiO3 and polycrystalline bulk CaCu3Ti4Ol2 were prepared successfully by Sol- Gel process and solid- state reaction, respectively, the dielectric properties for both materials are investigated systematically. The experiment results show that the dielectric properties of BaTiO3 bulk ceramics are very sensitive to the temperature. At room temperature, in the range of frequency 200 - 150 000 Hz, its dielectric constant is almost unchanged and as high as 2 967, its dielectric loss is very low so that it can be used to fabricate some electric device. While the dielectric constant e of polycrystalline bulk CaCu3Ti4O12 is as high as 14 000 at T = 300 K and f= 1 kHz. More over, the value of e remains constant in the range of temperature 100 - 350 K. Comparing the dielectric properties of the two materials, polycrystalline bulk CaCu3Ti4O12 will have more advantages in practical applications due to its high dielectric constant, insensitive to temperature and low dielectric loss.