Evaluation of Nanocrystalline Magnetic ErFeO₃ Composite for the Sorptive Removal of Cesium and Cobalt Ion from Aqueous Solution

The effect of nano-scale size in the magnetic semiconductor rare Earth ferrite system, ErFeO 3 , has been studied. The orthorhombic crystal structure in the nano-scale was found for ErFeO 3 prepared by the sol-gel method to be 8 nm. Fe-O stretching vibration was identified in the IR band at around 561 cm −1 , whereas the O-Fe-O deformation vibration was identified in the band at about 437 cm −1 . The semiconducting behavior of ErFeO 3 was found, and its energy gap equals 1.75 eV. As the frequency increases, the charge transport mechanism showed transition from the small polaron model, dominated by thermally activated hopping, to a quantum mechanical tunneling model, where charge carriers move through the material by tunneling between localized states without trapping. This transition is driven by the charge carriers having less time to become localized at higher frequencies, allowing for more direct tunneling transport. The new application of nano-crystalline ErFeO 3 to remove hazardous elements was evaluated. The adsorption isotherm of Cs(I) and Co(II) by ErFeO 3 nanocomposite was studied. The findings of the present studies highlight the potential use of ErFeO 3 as a new, efficacious sorbent for removing Cs(I) and Co(II) from the waste stream, providing a reliable and efficient solution to environmental pollution.