We report the effect of In on superparamagnetic CoIn_xFe_2-xO₄ (x = 0.00, 0.05, 0.10 and 0.15) nanoparticles (NPs) prepared through one step hydrothermal method. The trace of In ions in the matrix causes to change the structural and magnetic properties of CoFe₂O₄ which is confirmed by XRD and magnetic analyses. X-ray diffraction (XRD) investigation along with the infrared spectroscopy exposed the formation of single cubic phase ferrite. The crystallite size decreased from 18.6 to 12.8 nm with the increase of In content. The particles size measured from SEM images were in the range of 40 to 24 nm depending on In content. The vibrating sample magnetometer (VSM) characterization at room temperature (RT) showed the typical superparamagnetic nature of the samples. This superparamagnetism arises due to size effect and single domain nature of the particles. The maximum saturation magnetization (M_s) for CoFe₂O₄ is 59.02 emu g⁻¹ which is much higher than the value (44.3 emu g⁻¹) obtained by coprecitation method. Such superparamagnetic CoIn_xFe_2-xO₄ nanoparticles obtained in this study may find practical applications for hyperthermia treatment and biosensors.

我们报告了In对通过一步水热法制备的超顺磁性CoIn _x Fe _2-x O ₄（x = 0.00、0.05、0.10和0.15）纳米颗粒（NPs）的影响。基质中In离子的痕迹会改变CoFe ₂ O ₄的结构和磁性XRD和磁分析证实了这一点。X射线衍射（XRD）研究与红外光谱一起揭示了单立方相铁氧体的形成。随着In含量的增加，晶粒尺寸从18.6nm减小到12.8nm。取决于In含量，从SEM图像测量的粒径在40至24nm的范围内。室温（RT）的振动样品磁力计（VSM）表征显示了样品的典型超顺磁性。这种超顺磁性是由于颗粒的尺寸效应和单畴性质而产生的。CoFe ₂ O ₄的最大饱和磁化强度（M _s）为59.02 emu g ^-1，远高于其值（44.3 emu g ^-1）通过共沉淀法获得。在这项研究中获得的此类超顺磁性CoIn _x Fe _2-x O ₄纳米粒子可能会在热疗和生物传感器中找到实际应用。