Plant-Mediated Green Synthesis of Zinc Ferrite Nanoparticles: Mechanisms, Properties, and Advanced Applications in Environmental and Biomedical Fields

Recently, plant-mediated green synthesis has emerged as a sustainable, eco-friendly, and cost-effective strategy for synthesizing zinc ferrite (ZnFe₂O₄) nanoparticles (NPs). This review critically examines the advancements in biosynthesizing ZnFe₂O₄ NPs using various plant extracts, including Aloe vera, Hibiscus rosa-sinensis, Aegle marmelos, Eucalyptus leaves, Tragacanth gum, Piper nigrum, and Moringa oleifera, among others. It emphasizes their dual role as reducing, capping, chelating, and stabilizing agents. The article extensively compares physicochemical properties of the green-synthesized NPs in terms of crystallite size, morphology, magnetic behavior, and band gap energy. Achieved through different synthesis routes such as sol-gel, hydrothermal, co-precipitation, and microwave-assisted methods. Special attention is given to the roles of phytochemicals, reaction conditions (pH and temperature, etc.), and post-treatment parameters in tuning the properties of NPs. Moreover, the review highlights the multifunctional applications of bio-synthesized ZnFe₂O₄ NPs in photocatalytic degradation of organic dyes, antimicrobial activity against pathogenic strains, anticancer uses, and their integration as anode materials in lithium-ion batteries. Through a structure-function correlation analysis, this study establishes ZnFe₂O₄ NPs as a promising platform for green nanotechnology, with significant implications for environmental remediation and biomedical innovation.