Green synthesis of silver nanoparticles from southern Eucalyptus globulus: Potent antioxidants and photocatalysts for rhodamine B dye degradation

Abstract

Nanotechnology and nanoscience provide innovative foundations for delivering a wide range of new and enhanced technologies to the modern world. To break down Rhodamine B (RhB) dye solutions, this work describes the creation of silver nanoparticles (Ag-NPs) using the aqueous leaf extract of Eucalyptus globulus (E. globulus). The biosynthesized Ag-NPs were studied using UV–vis spectroscopy and SEM in conjunction with EDX, TEM, FTIR, HPLC and XRD. Stable Ag-NPs were synthesized using E. globulus, as evidenced by the absorption peaks at 431 nm seen in the UV–vis spectrum analysis. Spherical-shaped particles were visible in the SEM images, and the metallic form of the synthesised Ag-NPs was verified by EDX. The initial concentration of RhB, reaction duration, temperatures, and pH were all adjusted to optimise the photocatalytic degradation of RhB using Ag-NPs. The results indicated that photocatalytic effectiveness increased with rising pH. After 80 min at room temperature, the degradation reached 91.20 % at pH 12. The antioxidant EC50 results demonstrate that Ag-NPs exhibited a higher level of protective antioxidants (20.15 ± 0.3 µg/mL for DPPH and 10.24 ± 0.2 µg/mL for ABTS) compared to the E. globulus leaf extracts.