La、V掺杂对SrBi_4Ti_4O_(15)性能影响对比研究

A comparison study on influences of La, V doping on properties of SrBi_4Ti_4O_(15)

采用传统固相烧结工艺,制备了掺杂量分别为0.00～1.00、0.00～0.06的La、V掺杂SrBi4Ti4O15铁电陶瓷。X射线衍射结果显示,La、V对SrBi4Ti4O15的A、B位掺杂都未影响材料的晶体结构。A、B位掺杂均改善了材料的铁电性能。La掺杂量为0.25时,SBTi的剩余极化(2Pr)增大50%,同时矫顽场(2Ec)下降了25%。少量的V取代SBTi的B位Ti离子后,2Ec虽无明显变化,但2Pr却可增大近两倍,并且不影响材料的居里温度,而A位掺杂导致了材料的居里温度的明显下降。这与A、B位掺杂对材料晶格畸变程度的影响有关。

Using the solid-state reaction method, La and V-doped SrBi_4Ti_4O_(15) ferroelectric ceramics were prepared with the doping content ranging from 0.00 to 1.00, 0.00 to 0.06, respectively. X-ray diffraction patterns showed that the crystal structure of SrBi_4Ti_4O_(15) was not affected by La-doping in A site nor V-doping in B site. Doping in A or B site improved the ferroelectric properties of SrBi_4Ti_4O_(15). The 2P_r of SrBi_4Ti_4O_(15) was enlarged by nearly 50% with La content at 0.25. Meanwhile, the 2E_c was decreased by about 25%?When Ti ions in B site were substituted by V ions, the 2E_c varied little, but the 2P_r increased to a very large value, which is nearly twice greater than that at zero doping. The Curie temperature behaved a very small shift to lower temperature upon V-doping in B site, and it decreased obviously upon La-doping in A site. These were related to the effect of doping in A or B site on the structure distortion.