Abstract In this study, SrFe 12 − x Tb x O 19 (0.00 ≤ x ≤ 0.1) hexaferrites (HFs) were prepared successfully by citrate sol-gel approach. X-ray powder diffraction analyses affirm the hexagonal structure of products. Impurity phase starts to appear for x ≥ 0.04. The crystallites sizes were estimated to be in the range of 33–46 nm. All the products exhibit inhomogeneous distribution of grain size detected through SEM. The analyses of magnetization versus applied magnetic field, M(H), were performed. Magnetization measurements were done at room (300 K; RT) and low (10 K) temperatures. The different magnetic parameters including saturation magnetization Ms, remanence Mr, squareness ratio (SQR = Mr/Ms), coercivity Hc, and magnetic moment n B are deduced and discussed in detail. At both considered temperatures, M(H) results show ferrimagnetic nature for all compositions. It is shown that the Tb substitutions significantly affect M(H) data. A significant increase in the Ms, Mr, and n B is observed for x = 0.02 sample. The SQR values are around 0.5 indicating the single domain nature with uniaxial anisotropy. The obtained magnetic results were investigated deeply with relation to structural and microstructural properties. Mossbauer spectroscopy results were also investigated. According to Mossbauer results, the Tb3+ ions preferentially occupy 12k and 4f2 sites.

中文翻译：

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Tb3+ 取代的锶六铁氧体：结构、磁性和光学研究以及阳离子分布

摘要 本研究采用柠檬酸盐溶胶-凝胶法成功制备了SrFe 12 - x Tb x O 19 (0.00 ≤ x ≤ 0.1) 六铁氧体(HFs)。X射线粉末衍射分析证实了产品的六方结构。当 x ≥ 0.04 时，杂质相开始出现。微晶尺寸估计在 33-46 nm 范围内。所有产品都表现出通过 SEM 检测到的粒度分布不均匀。对磁化强度与外加磁场 M(H) 进行了分析。在室温 (300 K; RT) 和低温 (10 K) 下进行磁化测量。推导并详细讨论了不同的磁参数，包括饱和磁化强度Ms、剩磁Mr、矩形比（SQR=Mr/Ms）、矫顽力Hc和磁矩nB。在两个考虑的温度下，M(H) 结果表明所有组合物都具有亚铁磁性。结果表明，Tb 取代显着影响 M(H) 数据。对于 x = 0.02 样本，观察到 Ms、Mr 和 n B 的显着增加。SQR 值约为 0.5，表明具有单轴各向异性的单畴性质。对获得的磁性结果与结构和微观结构特性进行了深入研究。还研究了穆斯堡尔光谱结果。根据 Mossbauer 结果，Tb3+ 离子优先占据 12k 和 4f2 位点。对获得的磁性结果与结构和微观结构特性进行了深入研究。还研究了穆斯堡尔光谱结果。根据 Mossbauer 结果，Tb3+ 离子优先占据 12k 和 4f2 位点。对获得的磁性结果与结构和微观结构特性进行了深入研究。还研究了穆斯堡尔光谱结果。根据 Mossbauer 结果，Tb3+ 离子优先占据 12k 和 4f2 位点。