La,V掺杂对Sr_2Bi_4Ti_5O_(18)性能影响对比研究

Study on contrast between influences of La,V doping on properties of Sr_2Bi_4Ti_5O_(18)

采用传统固相烧结工艺,制备了掺杂量分别为0.000~1.000,0.000~0.096的La,V掺杂Sr2Bi4Ti5O18铁电陶瓷.X射线衍射结果显示,La,V对Sr2Bi4Ti5O18的A,B位掺杂都未影响材料的晶体结构.La掺杂使得材料的剩余极化2Pr逐渐降低,而V掺杂可以显著地提高2Pr.A位掺杂导致材料的居里温度明显下降,而V取代B位Ti4+离子不影响材料的居里温度.微观照片显示,Sr2Bi4Ti5O18样品由呈四方状的晶粒组成,晶粒较为均匀.La掺杂未改变晶粒的形状,而V掺杂使得晶粒呈现扁平状,且晶粒尺寸明显增大.

Using the solid-state reaction method, La and V-doped SrBi_4Ti_4O_(15)() ferroelectric ceramics have been prepared with the doping content ranging from 0.000 to 1.000, 0.000 to 0.096, respectively. X-ray diffraction patterns show that the crystal structure of Sr_2Bi_4Ti_5O_(18) is not affected by La-doping in A site or V-doping in B site. Doping in A site decreases the remnant polarization of (SrBi_4Ti_4O_(15),) and doping in B site can enlarge the remnant polarization notably. The Curie temperature decreases with La-doping, while the substitution of V^(5+) for Ti^(4+) does not affect the Curie temperature. The grain of SrBi_4Ti_4O_(15) is orthogonal, which does not change after La-doping. After V-doping, the grain is plate-like and grows larger.