Effect of Sc3+ Doping on the Optical and Magnetic Properties of Cobalt Chromite Nanoparticles

The current study examines the structural, surface morphology, electrical, optical, and magnetic properties of [Co(1-x)Scx][Cr2][O4] (x = 0, 0.01, 0.03, 0.05, 0.07) prepared by combustion method. XRD (X-ray diffraction) and Raman spectra were utilized to confirm phase and structural. SEM (scanning electron microscopy) micrographs were utilized for the analysis of the surface morphology. AC conductivity and dielectric characteristics were utilized to investigate the electrical properties. UV–Vis DRS (UV–Vis diffuse reflectance spectroscopy) was used to investigate the optical characteristics. The development of spinel cubic structure is confirmed by XRD. The hopping lengths increase as the Sc3+ ion concentration rises. The extremely porous nature may be seen in all SEM images. The Koop’s phenomenological theory and hopping mechanism were utilized to explain dielectric properties. At higher frequencies, all samples have good AC conductivity and a low dielectric loss tangent. Optical experiments were conducted using a UV–Visible diffuse reflectance spectrometer to assess the energy gap and absorbance bands. The decrease in the energy gap as Sc3+ concentration rises could be explained by an increase in the lattice parameter due to an increase in Sc3+ concentration. The dc-susceptibility study reveals two magnetic transitions such ferrimagnetic (FIM) order transition below Curie temperature (Tc) and spiral spin order transition at spiral transition temperature (Ts). The scandium-doped [Co][Cr2][O4] samples show negative magnetization below compensation temperature (Tcomp). The obtained results from M-H loop at 25 K, 95 K, and 300 K agree well with the magnetic transitions obtained from the temperature-dependent susceptibility study.