A Comparative Study of Synthesis and Characterization on La2FeMnO6 and La2NiMnO6 Double Perovskite Nanoparticles

Abstract Double perovskite nanoparticles of La2FeMnO6 and La2NiMnO6 were effectively prepared using combustion synthesis method. X-Ray Diffraction (XRD) and Selected Area Electron Diffraction (SAED) studies verified the formation of the double perovskite phase, with well-defined 2θ peaks corresponding to the respective crystallographic (hkl) planes. The crystallite size was estimated to be in the range of 19–25 nm. High-Resolution Transmission Electron Microscopy (HR-TEM) images revealed a predominantly spherical morphology with uniform particle distribution. Energy Dispersive X-Ray (EDX) spectra confirmed the elemental composition, confirming the presence of La, Fe, Mn, O in La2FeMnO6 and La, Ni, Mn, O in La2NiMnO6 nanoparticles. The optical band gaps were estimated to be 1.70 and 1.72 eV for La2FeMnO6 and La2NiMnO6, respectively. Fourier Transform Infrared Spectroscopy (FTIR) spectra showed characteristic vibrational bands at 425, 588, 870, and 1029 cm–1, corresponding to La3+–O2–, Fe3+–O2–, Mn3+–O2–, and Ni3+–O2– bonding vibrations. Magnetic hysteresis measurements indicated that La2FeMnO6 exhibits weak diamagnetic behavior, while La2NiMnO6 shows paramagnetic characteristics.