Ta掺杂钛酸镧陶瓷的铁电和介电性能研究

Study on Ferroelectric and Dielectric Properties of Ta-Doped Lanthanum Titanate Ceramics

采用传统固相反应法制备La2Ti2-xTaxO7(Ta摩尔分数x=0、0.1、0.2、0.3)陶瓷,对其晶体结构、表面形貌、铁电性能和介电性能进行了研究,实验结果表明,Ta掺杂La2Ti2O7陶瓷,Ta5+取代B位的Ti 4+,形成La2Ti2-xTaxO7固溶体,提高钛酸镧陶瓷的铁电和介电性能,在x=0.2时,La2Ti2-xTaxO7陶瓷的铁电性能和介电性能达最大值(剩余极化强度Pr=0.3μC/cm2,介电常数εr=5 600)。同时研究发现该陶瓷在高频区性能稳定。

La2 Ti2-xTax O7 （x= 0.0, 0.1, 0.2, 0.3） ceramic were prepared by conventional solid state reaction method. The crystal structure, surface morphology, ferroelectric and dielectric properties of La2Ti2-xTaxO7 ceramics have been investigated. The experimental results indicate that the substitution of Ta^5＋ for Ti^4＋ at B site to form La2 Ti2-xTaxO7 solid solution can significantly enhance the ferroelectric and dielectric properties of La2 Ti2 O7 ceramics. At x=0.2%, ferroelectric and dielectric properties of La2Ti2 -xTaxO7 ceramics reach the maximum values （Pr =0. 3 μC/cm2 ,ετ=5 600）. Dielectric properties of La2Ti2-xTaxO7 ceramics are stable in the high-frequency.