Structural, magnetic, dielectric properties of double perovskite- La2NiFeO6 synthesized by wet chemical route

The polycrystalline double perovskite La₂NiFeO₆ nanocrystallites were synthesized using the wet chemical sol–gel method. X-ray diffraction (XRD) analysis confirmed the formation of a single-phase material with a monoclinic P_21/n structure and an estimated crystallite size of 17 nm. Selected Area Electron Diffraction (SAED) patterns revealed the presence of diffraction rings, further indicating the monoclinic structure. Dielectric and impedance studies, conducted as functions of temperature and frequency, highlighted the contributions of grains and grain boundaries to the relaxation processes. The AC conductivity values ranged from 2.45 × 10^–5 S/m to 5.51 × 10^–5 S/m S/m over a temperature range of 300 K to 473 K at a frequency of 2 kHz. Notably, La₂NiFeO₆ exhibits novel ferromagnetic semiconductor properties and undergoes a spin glass transition at approximately 50 K. This comprehensive investigation provides the first report on the structural, dielectric, and magnetic properties of La₂NiFeO₆, underscoring its potential as a promising material for advanced data storage and spintronic device applications.