Synthesis of Lanthanum Ferrite Perovskite Nanoparticles: An Alternative Bio-Approach Versus a Conventional Chemical Approach

Herein, we report the synthesis of perovskite-type oxide LaFeO3 nanoparticles via chemical as well as bio approaches. Azadirachta indica (neem) extract's impact on the LaFeO3 nanoparticles has been studied to identify potential substitutes for detrimental chemical synthesis. The X-ray diffraction (XRD) examinations of synthesized perovskites by both routes reveal the cubic LaFeO3 phase and identical crystallographic patterns. The optical bandgap energies (Eg) for the chemical and bio-synthesized variants are determined to be 2.05 and 2.03 eV, respectively using UV-visible (UV-vis) spectroscopy. Fourier transform infrared spectroscopy (FTIR) analysis affirms the occurrence of two significant vibrational bands at 558 and 438 cm(-1), which strengthen the formation of perovskite LaFeO3. Field emission scanning electron microscopy (FE-SEM) investigation indicates the chemical variant has larger blockier-shaped particles, whereas the bio-synthesized sample has a micro-spherical morphology with sharp edges. The X-ray photoelectron spectroscopy (XPS) investigations substantiate the chemical state of La-3d, Fe-2p, and O-1s present in both variants, which comprises the 3 : 3 perovskite type. Vibrating Sample Magnetometry (VSM) analysis elucidates weak ferromagnetism at room temperature in both of the synthesized samples. The novelty of this work concentrates on divulging that green synthesized LaFeO3 perovskites are more environmentally benign and affordable than chemically synthesized ones.