Sphere-like Nb2O5 nanoparticles by waste Brassica oleracea leaf extract for lead removal and photocatalytic degradation of methylene blue dye

Currently, water-soluble pollutants such as hazardous chemicals and pigments create severe environmental hazards. Heavy metals such as lead, chromium, mercury, and arsenic were dangerous to living beings even at very low levels. To overcome this limitation, Nb₂O₅ nanoparticles were created utilizing a novel green approach. Based on plant components, green technique is a low-cost, safe, and environmentally good solution. In the present inquiry, we employ phytonutrients from waste Brassica oleracea leaf juice as a capping and reducing component. The product was evaluated using XRD, FT-IR, UV, SEM, and TEM techniques. The findings showed that the produced Nb₂O₅ NPs had a sphere-like geometry having a median particle dimension of 9 nm confirmed by XRD analysis. SEM study reveals ultrafine, homogeneous morphological agglomerations and uniform granules in TEM analysis, 10–15 nm particles predicted by crystallography, orthorhombic Nb₂O₅ (001) planes matching 0.39 nm lattice edge measurement error, and a clearly defined SAED diffract signal implying polycrystalline calcined powder. Excitation absorbance bands at 350 nm may be caused by charged balancing in the Nb–O–Nb architecture increasing oxygen concentration confirmed by UV–Vis analysis. The Nb₂O₅ nanosphere has a surface area of 120 m²/g, 0.592 cm²/g of pores, and a mean pore dimension of 15.2 nm, determined using Barrett-Joyner-Halenda (BJH). A sequential Adsorption capacities assay shown that it is an effective absorber used to eliminate Pb (II) ions from aqueous solutions. Adsorbents was able to be readily removed from the resultant fluid and recycled repeatedly. The produced Nb₂O₅ Nanoparticles are capable of removing toxic heavy metals and synthetic colors from polluted waterways.