Ag/ZnO/Plant Extract Green Nanocomposite: A Review on Its Antibacterial, Antioxidant, Adsorption and Photocatalytic Potentials
DOI:
https://doi.org/10.64354/yc8tj665Keywords:
Silver nanoparticles , Zinc oxide , Plant extract , Antibacterial , Green synthesisAbstract
Hybrid nanomaterials made of noble-metal nanoparticles, semiconducting metal oxides, and bioactive plant extracts are gaining popularity as sustainable multifunctional materials. Silver nanoparticles have a strong antimicrobial action and a localised surface plasmon resonance (LSPR) that extends light absorption into the visible region, ZnO has a wide-band-gap semiconductor with intrinsic antibacterial and photocatalytic activity, and the plant extract often acts as a reducing and capping agent. This review summarises the published literature on this composite with a focus on four functions: antimicrobial activity against Gram-positive and Gram-negative bacteria, antioxidant activity mostly determined by DPPH and ABTS assays, dye and heavy-metal adsorption from aqueous solutions, and photocatalytic degradation of organic pollutants under UV and visible light. The most popular synthesis processes-one-pot bio-mediated assembly, sequential green precipitation and post-impregnation are summarised and their effect on morphology, crystallinity and band gap is explored. Reported figures demonstrate clear synergistic enhancement compared with single-component or binary systems. In particular, under visible-light irradiation, the Ag-ZnO Schottky junction minimises electron-hole recombination. We also discuss practical prospects and limitations for future study, including Ag leaching, variability of plant extracts, long-term stability, and potential cytotoxicity.
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