Abstract In this study, nano-sized particles of BaCrxFe12−xO19 (0.0 ≤ x ≤ 1.0) hexaferrite were fabricated through citrate auto gel combustion process and the impact of Cr-ion substitution on ac magnetic susceptibility properties of Ba-hexaferrite were explored. X-ray powder diffraction (XRD) measurements approved the purity of prepared samples and showed a reduction of the average crystallite size with increasing the content of Cr. Transmission electron microscopy (TEM) observation indicated the hexagonal morphology of all samples. AC susceptibility measurements displayed a frequency dependence of the magnetic responses. These measurements indicated that there are strong magnetic interactions (which is the highest for BaCr0.3Fe11.7O19 NP) between particles which cause a superspin glass-like (SSG) behavior at low temperatures. Estimating the values of loss power density revealed an increase of loss power density with increasing Cr-substitution element. The relative sensitivity of the prepared MNPs to the variation of applied frequency is very influenced by Cr-substitution and is highest in BaCr0.3Fe11.7O19 MNPs, suggesting that this sample can be considered as magnetic nanomaterial for hyperthermia and for many other applications.

中文翻译：

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Cr 3+ 取代对六铁氧体Ba纳米颗粒交流磁化率的影响

摘要 本研究通过柠檬酸盐自凝胶燃烧法制备了BaCrxFe12−xO19纳米颗粒(0.0≤x≤1.0)六铁氧体，并探讨了Cr离子置换对Ba-六铁氧体交流磁化率性能的影响。X 射线粉末衍射 (XRD) 测量证实了制备样品的纯度，并显示平均晶粒尺寸随着 Cr 含量的增加而减小。透射电子显微镜 (TEM) 观察表明所有样品的六边形形态。AC 磁化率测量显示了磁响应的频率依赖性。这些测量表明粒子之间存在强磁相互作用（对于 BaCr0.3Fe11.7O19 NP 是最高的），这会在低温下导致超自旋玻璃样 (SSG) 行为。估算损耗功率密度的值表明损耗功率密度随着 Cr 取代元素的增加而增加。制备的 MNPs 对施加频率变化的相对敏感性受 Cr 取代的影响很大，并且在 BaCr0.3Fe11.7O19 MNPs 中最高，表明该样品可以被认为是用于热疗和许多其他应用的磁性纳米材料。