Nanoparticle-encapsulated organo-magnetogels: crosslinked network for broad-spectrum pollutant removal

In this contribution, we report the synthesis of a poly(4-vinylpyridine)-reduced graphene oxide-magnetite (P4VP-rGO-Fe₃O₄) organo-magnetogel (OMG), designed for high-performance pollutant adsorption. In the OMG, rGO and Fe₃O₄ nanoparticles are in situ encapsulated during the chemical cross-linking of the 4-vinylpyridine polymer. The adsorption performance of OMG was evaluated using three model water pollutants, viz., organic dyes, heavy metal ions, and waterborne pathogens. The equilibrium adsorption capacity exceeded 400 mg/g for the organic dyes. Beyond dye removal, the OMG also adsorbed heavy metal ions, such as AsO₂⁻, Pb²⁺, Cr₂O₇^2−, and Cd²⁺ ions, with removal efficiencies exceeding 60% and adsorption capacities exceeding 200 mg/g. The OMG also exhibited remarkable antibacterial activity against E. coli and S. Typhi, with almost zero viability for S. Typhi. The OMG promises a broad-spectrum applicability in wastewater treatment, offering a sustainable and efficient solution for water decontamination.