Impact of Ni Substitution on the Structural, Optical and Electronic Behavior of La<sub>2</sub>CrMnO<sub>6</sub> Double Perovskite for Energy Applications

Poly-crystalline double perovskite La2Cr1−xNixMnO6 (x = 0.00, 0.50, 1.00) has been synthesized by solid state reaction (SSR) method. Structural properties of La2Cr1−xNixMnO6 have been investigated using X-ray diffraction (XRD). The XRD pattern confirmed the single-phase formation of the orthorhombic structure having Pbnm symmetry. The morphological analysis of the synthesized sample was conducted using Scanning Electron Microscopy (SEM). The average particle size, determined from SEM micrographs, is 2 μm (x = 0.00), 1.56 μm (x = 0.50), and 1.32 μm (x = 1.00), indicating a progressive decrease in particle size with increasing nickel doping. The optical characteristics of the samples have been examined using UV-visible spectroscopy. The band gap has been found to be decreased with Ni doping. The XPS analysis verifies the presence of all elements at their respective binding energies and shows the splitting of Cr and Ni ions, which is attributed to spin-orbit coupling. The tuning of the optical band gap and the reduction in particle size in Ni-substituted La2CrMnO6 emphasize its potential for advancing future technological and energy applications.