Facile Synthesis of MgO/CuO and MgO/Cu₃MgO₄ Binary Nanocomposites as Promising Adsorbents for the Disposal of Zn(II) Ions

Water pollution is a pressing environmental issue that affects water sources such as lakes, rivers, groundwater, and oceans. It arises from the introduction of harmful substances, including heavy metals and chemicals, into water sources, posing significant risks to both human health and aquatic ecosystems. Prolonged exposure to Zn(II) ions carries substantial health hazards, such as nausea, vomiting, hemolysis, reduced hemoglobin levels, and abdominal pain. Consequently, this study employed the Pechini sol-gel method to facilely create MgO/Cu3MgO4 nanostructures at 900 & DEG;C and MgO/CuO nanostructures at 500 and 700 & DEG;C. The nanostructures, which were synthesized at 500, 700, and 900 & DEG;C, were abbreviated as MC500, MC700, and MC900, respectively. In this method, tartaric acid reacts with Mg(II) and Cu(II) ions to form chelates. In addition, ethylene glycol was used as a crosslinker to form polymer networks, which were finally ignited at different temperatures to remove organic parts and produce nanostructures with small crystal sizes and high surface areas. The synthesized nanostructures were characterized by XRD, HR-TEM, EDS, FE-SEM, and N-2 adsorption/desorption analyzer. The XRD revealed that the MC500, MC700, and MC900 nanostructures exhibit average crystallite sizes of 89.80, 78.43, and 69.05 nm, respectively. Besides, the MC500, MC700, and MC900 nanostructures exhibit BET surface areas of 33.23, 39.38, and 42.20 m(2)/g, respectively. The greatest removal capabilities of the MC500, MC700, and MC900 nanostructures for Zn(II) ions were found to be 295.86, 324.68, and 361.01 mg/g, respectively. Also, the adsorption processes of zinc ions on the MC500, MC700, and MC900 nanostructures were exothermic, spontaneous, chemical, and more accurately described by the pseudo-second-order model and Langmuir isotherm. The synthesized nanostructures were regenerated and reused several times to remove zinc ions without losing their efficiency. Thus, the use of these nanostructures is excellent from an economic point of view in terms of ease of preparation, high efficiency in removing zinc ions, ease of regeneration and reuse, and safety.