摘要
采用高温固相法制备了铌掺杂Bi3.15Nd0.85Ti3O12铁电材料.利用X射线衍射仪、拉曼光谱仪分析样品物相结构,阻抗分析仪和铁电性能测量仪测试电性能.发现制备的陶瓷材料均为单一的层状钙钛矿结构,反映TiO6八面体内部振动情况的850cm-1处拉曼峰随着Nb掺杂量的增加明显上移,表明:TiO6参与取代过程,Ti4+被具有较小离子半径的Nb5+取代.Nb的引入使样品的介电损耗明显降低,居里温度呈下降趋势.随着Nb掺杂量的增加,材料的剩余极化强度先增大后减小,当x=0.03时2Pr达到极大值19.3μC/cm2,矫顽场为57.5 kV/cm.
Nb-doped Bi3.15Nd0.85Ti3-xNbxO12＋x/2 layer-structured ferroelectric ceramics are prepared by the solid-state reaction method. The microstructures of the samples are analyzed by X-ray diffraction and Raman spectra. The dielectric and ferroelectric properties of samples are investigated. It was found that all the polycrystalline ceramics have almost a single phase. The Raman phonon mode at 850cm^-1 shifts higher with the increase of niobium content, which originates mainly from the vibrations of atoms inside the TiO6 octahedron. It indicates that the Ti^4＋ ions are substituted by Nb^5＋ ions with less ion radius, and there is structural distortion of the oxygen octahedral. By Nb^5＋ doping, the loss tangents of Bi3.15Nd0.85Ti3-xNbxO12＋x/2 ceramics are much lower, and the Curie temperature decreases. At a small Nb doping of x =0.03, the remanent polarization （Pr） increases. The 2Pr and coercive field of the sample （x = 0.03） are 19.3μC/cm^2 and 57.5 kV/cm respectively.
出处
《重庆工学院学报（自然科学版）》
2009年第6期107-110,共4页
Journal of Chongqing Institute of Technology
基金
山西省自然科学基金资助项目(2007011061)
山西省科技攻关项目(2007031141)
