Magnetically driven, plant-extract-modified Fe ₃ O ₄ nanoparticles for sustainable and eco-friendly wastewater detoxification: recent developments

The increasing burden of toxic heavy metals, dyes, pharmaceuticals, and pathogenic microorganisms in aquatic environments necessitates the development of sustainable purification strategies. This review comprehensively elucidates recent progress in the synthesis, characterization, and application of phytogen-based synthesis of functionalized magnetic nanoparticles (phytogen@MNPs) for eco-friendly wastewater treatment. Plant-derived bioactive compounds serve as green capping agents, facilitating the synthesis of multifunctional, biocompatible, and surface-reactive MNPs. This review details diverse phytogenic sources, synthesis methodologies, and advanced characterization techniques, highlighting the influence of surface modification on stability, adsorption efficiency, and superparamagnetic behavior. Applications in the adsorption and catalytic degradation of inorganic, organic, and microbial contaminants are critically discussed, along with the kinetics, isotherms, and thermodynamics of pollutant removal. The antibacterial properties, reusability, and impact of real water matrices are covered, highlighting the superior performance and cost-effectiveness of phytogen@MNPs. Mechanistic insights into pollutant-nanoparticle interactions reveal the decisive roles of surface functionalization and particle size. This review also encompasses the advantages of phytogen@MNPs over conventional materials, while also identifying the need for standardized protocols, evaluation of long-term stability, and strategies for scalable production to fully realize their potential in environmental remediation in future work.