Structural, vibrational, and magnetic properties of Bi1-χTbχFeO3 (0≤χ≤0. 2) prepared by sol-gel method were studied by combining X-ray diffraction, Raman scattering, and physical properties measurement. It was found that partial substitution of Tb (χ=0. 10— 0. 125) at Bi site results in a structural transformation from the rhom-bohedral R3c symmetry to the orthorhombic Pnma phase, accompanied by a ferroelectric-paraelectric phase transition. In addition, with increasing Tb concentration, the remnant magnetization Mr rises gradually and reaches a maximum of ' 0. 223emu/g, which is about seven times more than that of the pure BiFeO3, at the polar-nonpolar phase boundary (χ=0. 10). Mr exhibits a gradual decrease with further increasing Tb concentration (χ≥20. 125), which is attributed to the anti-parallel alignment of magnetic moments in orthorhombic sample.%采用溶胶-凝胶法制备了Tb掺杂的BiFeO3粉晶,其掺杂浓度为0≤x≤0.2,分别用X射线衍射仪、Raman散射仪和综合物性测量系统对Bi1-xTbxFeO3粉晶样品的结构、Raman活性振动模式和磁性进行了测量和分析.实验结果表明:当Tb掺杂量x在0.10～0.125时,母体BiFeO3的结构由菱形R3c相变为正交Pnma相,同时伴随着铁电-顺电相的变化.另外,随着掺杂浓度的增大,Bi1-xTbxFeO3的磁性逐渐增强,并且在铁电-顺电相相变边界处(x=0.10),剩余磁化强度Mr达到最大值0.223emu/g,约为纯相BiFeO3的8倍.随着Tb掺杂量进一步增大(x≥0.125),样品的剩余磁化强度开始逐渐减小,其原因是在正交相的样品中磁矩逐渐形成了很好的反平行排列.
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