Preparation and spectroscopic investigations of nickel oxide as a highly efficient catalytic porous nanomaterial for use in the removal of colored and heavy materials

In recent years, the need for safe and economical ways to eliminate waste materials from contaminated water has necessitated directing much scientific research towards the production of low-cost alternatives for activated carbon that are commercially available. Herein, in this study, nickel (II) 4-aminohippurate complex, [Ni(4AHPA)2(H2O)2]4H2O, was microwave-assisted synthesized as a precursor to prepare nickel oxide nanoparticles (NiO-NPs). The precursor complex was characterized by elemental analyses (CHN), spectroscopic studies, and measurements of magnetic susceptibility as well as thermal analysis. X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy were used to identify the NiO-NPs. To remove Rhodamine B dye (RhB) from an aqueous solution, NiO-NPs were utilized. Investigated were the effects of contact time, adsorbent dose, and pH. The oxide nanomaterial showed an adsorbent removal effectiveness of 82% for RhB dye in an aqueous solution. Because of their large surface area and nanosize, NiO-NPs demonstrated remarkable catalytic applications. Metal oxide nanoparticles have large surface areas for their size and can be easily linked with various chemicals, and are then removed using a magnet. This study is to contribute to the search for less expensive adsorbents of the highest quality, and the possibilities of their use for the elimination of industrial dyes wastewater. KEY WORDS: Microwave-assisted synthesis, NiO-NPs, XRD, Spectroscopic, Photocatalytic activity Bull. Chem. Soc. Ethiop. 2026, 40(3), 627-639. DOI: https://dx.doi.org/10.4314/bcse.v40i3.10