变价铈离子对(Li,Ce)改性的铋层状化合物结构和性能的影响

Effect of Multivalence Cerium in Aurivillius Oxides with Lithium and Cerium Modification

为了明确变价铈离子对铋层状化合物结构和电学性能的影响机理,采用传统固相工艺制备了不同价态铈离子为原料的(Li,Ce)改性的Sr0.6-x(LiCe)x/2(BiNa)0.2Bi2Nb2O9(SBNBN)陶瓷.实验结果表明:不同价态的铈离子由于实际取代位置的不同,会引起材料不同的晶格畸变;不同价态铈离子对SBNBN陶瓷介电性能的影响也不同,Ce3+离子降低了材料的居里温度和高温介电损耗,Ce4+离子则提高了材料的居里温度和高温介电损耗;不同价态铈离子取代均能有效提高(Li,Ce)改性的SBNBN陶瓷的压电性能,Ce3+和Ce4+离子改性的SBNBN陶瓷压电系数的最大值分别达到了28pC·N-1和32pC·N-1.

In order to confirm the effect of multivalence cerium on structure and electric properties of the auvillius oxides,- Sr0. 6-x （LiCe） x/2 （BiNa） 0. 2 Bi2 Nb2 09 （SBNBN） ceramics with different valence cerium cations as starting materials were prepared by the conventional solid-state reaction method. Results indicated：The different lattice distortion was induced due to introduction of different valence cerium. Curie temperature and high temperature dielectric loss of SBNBN ceramic were suppressed as introduction of Ce3＋ ions but improved as Ce4＋ ions introduced. Piezoelectric properties of SBNBN ceramic were improved by （Li,Ce） modification. The maximum of piezoelectric coefficient was 28 pC · N-1 and 32 pC · N-1 for Ce3＋ and Ce4＋ ions modified SBNBN ceramics, respectively.