【摘要】 用溶胶-凝胶法制备出Sr₂Bi₅FeTi5O₂₁（SBFTi）铁电陶瓷,用FT-IR和DSC-TG分析前驱体凝胶和粉体随温度的变化。结果表明。SBFTi陶瓷的合成温度在721℃左右,粉体的预烧温度为600℃。XRD结果表明烧结后的陶瓷样品呈现钙钛矿结构,由于BiFeO₃（BFO）的加入使SBFTi与Sr₂Bi₄Ti₅O₁₈（SBTi）相比发生晶格畸变,晶面间距增大。SBFTi陶瓷样品铁电性能较好,在125 kV/cm电场强度下剩余极化强度2Pr和矫顽场强2Ec分别为20.5μC/cm²和128kV/cm,其铁电性能优于SBTi铁电陶瓷。更多还原

【Abstract】 A sol-gel method was used in synthesizing Sr₂Bi₅FeTi₅O₂₁（SBFTi） ferroelectric ceramic. Analyses of changes in precursor gels and powders by FT-IR spectrum and DSC-TG show that the SBFTi ceramic is synthesized at about 721 oC and the optimal pre-calcination temperature for powders is 600 oC. The XRD results indicate that sintered ceramic samples present bismuth layer-structured perovskite structure and the main crystal phase of SBFTi is Sr₂Bi₄Ti₅O₁₈（SBTi） with lattice distortion, which result from the addition of Bi FeO₃（BFO）. Besides, it is also found that the polycrystalline SBFTi ceramic exhibits good ferroelectric properties. The values of remnant polarization（2Pr） and coercive electric field（2Ec） are 20.5 μC/cm² and 128 kV/cm at an applied electric field of 125 kV/cm, respectively, which are better than those of the SBTi ceramic.更多还原