Magnetic Quaternary Nanocomposites Integrate PANI, Graphene Oxide, Chitosan, and ZrO₂/ZnO to Synergistically Photodegrade Methylene Blue and Adsorb Cd²⁺, Cr⁶⁺, and Ni²⁺ from Wastewater

This study reports the synthesis of magnetic quaternary nanocomposites based on polyaniline, graphene oxide, chitosan, Fe₃O₄, and metal oxides (ZrO₂ or ZnO) via an in-situ polymerization approach. The structural, optical, and morphological properties of the synthesized nanocomposites were investigated using UV–Vis spectroscopy, X-ray diffraction, and scanning electron microscopy. Quantitative XRD analysis confirmed the nanocrystalline nature of the composites, while SEM analysis revealed a porous morphology with particle sizes mainly in the range of ۵۰–۲۰۰ nm.The photocatalytic performance was evaluated through methylene blue degradation under ambient laboratory light. The ZrO₂-based nanocomposite achieved approximately ۹۵% degradation of methylene blue (۵۰ ppm) after ۴۸ h, while the ZnO-based system showed about ۸۵% degradation under identical conditions. Heavy metal adsorption experiments analyzed by ICP-OES demonstrated effective removal of Cd²⁺, Cr⁶⁺, and Ni²⁺ ions, with removal efficiencies reaching up to ۸۸% for Cd²⁺ and improved selectivity toward Cr⁶⁺ and Ni²⁺ in the ZrO₂-containing composite.The results highlight the synergistic role of the quaternary structure in combining photocatalytic activity, adsorption capability, and magnetic recoverability within a single platform. These multifunctional nanocomposites show promise for integrated wastewater treatment applications involving both organic dyes and toxic metal ions.

کلیدواژه ها:

polyaniline nanocomposites ، Photocatalysis ، Heavy Metal Adsorption ، Graphene oxide ، Magnetic materials