【摘要】 利用溶胶凝胶结合自蔓延燃烧法合成了稀上Gd与Zn/Mn掺杂的纳米钡铁氧体,XRD结果显示合成的所有样品都呈现磁铅石的主相结构。合成样品的磁学性能由振动样品磁强计进行表征,结果显示材料相结构与磁性能主要取决于掺杂元素的种类以及含量。由于受到12k与2b超精细场、Gd³⁺的自旋倾斜、磁稀释(Fe³⁺→Fe²⁺)以及杂相的共同作用,Gd掺杂样品的饱和磁化强度随着掺杂含量的增加先增大后减小,但是复合掺杂样品的饱和磁化强度则线性降低。样品矫顽力的变化主要受到掺杂元素以及含量的影响,Mn²⁺掺杂使矫顽力增加1,而Zn²⁺掺杂则使矫顽力减小。通过对合成的钡铁氧体样品磁性能的研究,可以判断Zn²⁺与Mn²⁺分别据4f₂和4f₁晶位。更多还原

【Abstract】 Rare earth ions Gd³⁺ combined Zn²⁺/Mn²⁺ substituted nanocrystalline barium hexaferrites were synthesized by the sol-gel auto-combustion process.The X-ray diffraction（XRD） indicated the major magnetoplumbite BaFe₁₂O₁₉ phase structure for all as-prepared samples.The static magnetic properties were characterized by Vibrating samples magnetometer（VSM）.All results showed that the phase composition and the magnetic properties were closely related to the kinds and amount of the doped elements.Owing to the combined actions of the intensive hyperfine field at 12 k and 2b sites,canting spins of Gd^3- themselves,magnetic dilution(Fe³⁺→Fe²⁺ in order to satisfy the principle of neutral electricity when Gd³⁺ substituted Ba²⁺) and impurity phases,the saturation magnetization（M_s） of Gd-substituted samples increased first with the doped amount（x）,and then decreased.But M_s for the other three samples almost decreased linearly with x.The coercivity（H_c） were critically affected by the different doped elements and amount x.The doped Mn²⁺ could make H_c increase,and the opposite results may be found for the Zn²⁺-doped samples.Compared the magnetic properties of all the samples,it was concluded that Zn²⁺ and Mn²⁺ occupied respectively 4f₂ and 4f₁ sites.更多还原