Comparative Structural, Vibrational, and Optical Properties of Ba(Ni₀.₅M₀.₅)O₃ (M = Cu, Co, Cr) Perovskites: A Study Using XRD, FTIR, and UV-Vis Spectroscopy

This study presents the synthesis and comparative analysis of Ba(Ni₀.₅Co₀.₅)O₃, Ba(Ni₀.₅Cu₀.₅)O₃, and Ba(Ni₀.₅Cr₀.₅)O₃ perovskite compounds, focusing on their structural, vibrational, and optical properties. The sol-gel method was employed to synthesize the materials, and X-ray diffraction (XRD) confirmed the formation of a cubic perovskite structure in all three compounds with high crystallinity. The calculated crystallite sizes were found to be in the nanometer range (24.77–29.53 nm), with slight lattice expansion observed for Cu and Cr substitutions. Fourier-transform infrared (FTIR) spectroscopy confirmed the presence of metal-oxygen bonds, characteristic of the perovskite structure, and indicated successful phase formation without impurities. UV-Vis spectroscopy revealed band gap energies of 2.68 eV for Ba(Ni₀.₅Co₀.₅)O₃, 2.92 eV for Ba(Ni₀.₅Cu₀.₅)O₃, and 3.18 eV for Ba(Ni₀.₅Cr₀.₅)O₃, suggesting their potential for optoelectronic and photocatalytic applications. These results demonstrate the efficacy of the sol-gel synthesis method in producing high-purity perovskite materials with desirable structural, vibrational, and optical properties, making them suitable for advanced technological applications such as photocatalysis, solar cells, and other optoelectronic devices.