The synthesis of nickel potasium ferrite (Ni_0·8K_0·2Fe₂O₄) nanoparticles with the doping of Monovalent K¹⁺ ions has been synthesized by sol-gel auto combustion method. Differential Thermal Analysis (DTA) was performed to analyze the phase formation of the prepared sample. The crystal phase formation has been confirmed by employing the XRD (X-ray diffraction) technique. The crystallite size and Strain were calculated by using the W–H (Williamson-Hall) plot. The crystallite of nanoparticles of K¹⁺ doped nickel ferrite is ∼30 nm. The FTIR spectra were recorded in the range of 560–590 cm⁻¹ to analyze the changes in nickel ferrite due to K¹⁺ ion manipulation. The optical property was studied in the field of 200 nm–1000 nm using UV visible spectrometer, and the results show that band gap was improved as in the case for nickel ferrite and the observed value was 2.20 eV, which was furthered decreased to 1.91 eV. The strong photoluminescence was observed in the visible range, and substitutions of monovalent potassium ion are improving its luminescence property. Its intensity peaks get shifted towards orange range 610 nm (2.03 eV). This shows that the monovalent ion may creates defects, leading to porosity and oxygen vacancy in the nanomaterial. The porous structure was confirmed by scanning electron microscope. The magnetic hysteresis loop has been recorded by employing the VSM (Vibrating Sample Magnetometer). The saturation magnetization and Curie temperature were found to increase with the substitution of monovalent potassium. Thus prepared material is soft magnetic nature, possess strong luminescence in the visible range, and high Curie temperature (798 K). Hence the present materials may be used as functional nanomaterials for various technological applications.

通过溶胶-凝胶自动燃烧法合成了掺有单价K ¹⁺离子的镍铁氧体（Ni _0·8 K _0·2 Fe ₂ O ₄）纳米粒子。进行差示热分析（DTA）以分析所制备样品的相形成。通过采用XRD（X射线衍射）技术已经确认了晶相的形成。微晶尺寸和应变是通过W-H（Williamson-Hall）图计算得到的。掺杂有K ^1+的镍铁氧体纳米颗粒的微晶为〜30 nm。FTIR光谱记录在560–590 cm ^-1范围内，以分析由于K ¹⁺引起的镍铁氧体的变化。离子操纵。使用紫外可见分光光度计在200 nm–1000 nm的范围内研究了光学性能，结果表明，带隙与铁氧体镍的情况一样有所改善，观察值为2.20 eV，进一步降低到1.91 eV 。在可见光范围内观察到强烈的光致发光，单价钾离子的取代改善了其发光性能。其强度峰移向610 nm（2.03 eV）的橙色范围。这表明单价离子可能产生缺陷，导致纳米材料中的孔隙率和氧空位。多孔结构通过扫描电子显微镜确认。磁滞回线已通过使用VSM（振动样品磁强计）进行了记录。发现饱和磁化强度和居里温度随一价钾的取代而增加。如此制备的材料具有软磁性，在可见光范围内具有强的发光性，并且居里温度高（798 K）。因此，本发明的材料可以用作用于各种技术应用的功能性纳米材料。