Rare earth (RE)-substituted magnesium–zinc ferrite (Mg_0.5Zn_0.5RE_xFe_2–xO₄) nanoparticles with different RE elements (Y, La, Ce, Pr, Nd, Gd and Yb) and different RE contents (x = 0–0.1) were synthesized via coprecipitation of metal hydroxides as the precursor, followed by calcination. Their crystal structures were characterized by X-ray diffraction (XRD) analysis, confirming that the RE-substituted Mg–Zn ferrites had a single-phase spinel structure at low x values. However, the Ce-substituted ferrites contained CeO₂ as a byproduct. Scanning electron microscopy (SEM) showed that the particle diameters of the samples decreased from approximately 100 to 20 nm as x was increased regardless of the RE elements. The magnetic induction heating properties were evaluated using the intrinsic loss power (ILP) determined from the temperature rise profiles in an alternating magnetic field and the amplitude and frequency of the magnetic field. By using various RE elements, it was found that the increase in the magnetic moment of RE ions can increase the magnetization of ferrites, resulting in improvements in the ILP at low RE contents, except for Gd substitutions. The increase in RE content decreased the ILP due to reductions in crystallinity. The results suggest that the RE elements and contents can precisely control the magnetic induction heating properties, and RE-substituted Mg–Zn ferrite nanoparticles are promising candidates for magnetic hyperthermia applications.

稀土（RE） -取代的镁-锌铁氧体（镁_{0 。5}的Zn _0.5 RE _X的Fe _{2- X} ö ₄）与不同的RE元素（Y，镧，铈，镨，钕，钆和Yb）和不同的RE的纳米颗粒 通过共沉淀金属氢氧化物作为前驱物，然后煅烧，可制得含量（x = 0–0.1）。通过X射线衍射（XRD）分析对它们的晶体结构进行了表征，证实了RE取代的Mg-Zn铁氧体具有低x值的单相尖晶石结构。但是，Ce取代的铁氧体含有CeO _2。作为副产品。扫描电子显微镜（SEM）表明，样品的粒径从约100降低到20nm作为X无论RE元素如何，都增加了。使用根据交流磁场中的温度上升曲线以及磁场的幅度和频率确定的固有损耗功率（ILP）来评估磁感应加热性能。通过使用各种RE元素，发现RE离子的磁矩的增加可以增加铁氧体的磁化，从而导致除了Gd取代以外在低RE含量下ILP的改善。RE含量的增加由于结晶度的降低而降低了ILP。结果表明，稀土元素和含量可以精确控制磁感应加热性能，稀土取代的Mg-Zn铁氧体纳米粒子是磁热疗应用的有希望的候选者。