Synthesis and characterization of nanoparticles from neem leaves and banana peels: a green prospect for dye degradation in wastewater

Nanoparticles have excellent catalytic, adsorptive, and reactive properties, which led to their application for wastewater treatment. The current study focuses on silver nanoparticle synthesis using neem leaf and banana peel extract and its application as an antimicrobial and dye degrading agent for wastewater treatment. The use of these extracts led to a rapid, simple, and environment-friendly method for the biosynthesis of silver nanoparticles (AgNPs). UV-Vis spectroscopy showed absorption bands at 473 and 423 nm for AgNPs synthesized from neem leaf and banana peel extracts, respectively. The AgNPs were further characterized using XRD, FTIR, ESEM, EDX, and DLS methods. XRD data confirmed the crystalline nature of the synthesized AgNPs. ESEM images revealed the synthesized nanoparticles were spherical. From DLS analysis the average diameter of the AgNPs was found to be 168.7 nm from banana peel and 206.4 nm from neem leaf extract. Antibacterial activity of synthesized nanoparticles at 0.025 mg/ml concentration was tested against Escherichia coli (E.coli), Bacillus subtilis (B.subtilis), Staphylococcus aureus (S.aureus), and Klebsiella sp. using disk diffusion method and the zone of inhibitions observed were 10–13, 3–4, 2–3, and 1–3 nm respectively. 99% degradation of model dye malachite green was observed using banana peels-derived nanoparticles at a concentration of 0.06 mg/ml within 4.5 h. This study provides an eco-friendly and economic approach to AgNP synthesis and its potential application in the removal of hazardous dye from wastewater.