Optimizing Magnetic, Optical, and efficient photocatalytic properties of chromite material for dye degradation

In this research, we have focused to examine en detail the microstructural, magneto-optical and photocatalytic behavior of the spinel chromite Ni _0.5 Cd _0.5 Cr ₂ O ₄ . The average crystallite size is around 73 µm, as verified by SEM analysis. Various magnetic parameters such as the saturation magnetization ( M _S ), coercivity ( H _C ), the anisotropy constant ( K) and squareness ratio ( SQ) was determined from hysteresis cycle. Subsequently, the optical properties were examined. The band gap energy (Eg) was estimated to be 2.52 eV using multiple methods, including the Tauc plot and the derivative method. Following the superposition of absorbance and reflectance spectra, a luminescent phenomenon was observed around 895 nm. Cauchy dispersion parameters were derived from the variation of the refractive index with wavelength, and the dispersion energy was evaluated using the Wemple–DiDomenico relation. Additional optical parameters—such as penetration depth, extinction coefficient, electrical conductivity, and plasma frequency—were analyzed as functions of wavelength. Furthermore, the photocatalytic potential of the synthesized material in degrading pollutants such as methylene blue was assessed, illustrating its applicability in environmental remediation. This comprehensive investigation provides a detailed understanding of the material’s multifaceted physicochemical properties.