Bio-mediated Synthesis of Silver Nanoparticles Utilizing Aqueous Leaf Extract of Lantana camera and Their Application as Nanophotocatalysts and Antimicrobial agents

This present study aimed toward the bio-mediated synthesis of silver nanoparticles (AgNPs) by utilizing aqueous leaf extract of Lantana camera with silver nitrate (AgNO3) as the precursor. The color transformation from light yellow to dark brown of the reaction media initially verified the synthesis of silver nanoparticles which was further confirmed by observing the characteristics Surface Plasmon Resonance (SPR) band peak of silver nanoparticles at 458 nm. The presence of any functional groups in silver nanoparticles was determined using Fourier Transformed Infrared (FT-IR) spectroscopy with the stretch of bonds of functional groups. Surface morphology and dispersity of nanoparticles were characterized with a Field-Emission Scanning Electron Microscope (FE-SEM) and the spherical polydispersed nanoparticles were observed with the particle sizes between 15 to 35 nm. The crystallinity and purity of AgNPs were revealed by X-ray Diffraction (XRD) analysis and Energy Dispersive Spectroscopy (EDS), respectively. Photocatalytic activity of AgNPs was observed against Methylene blue (MB) dye under solar light irradiation.The AgNPs efficiently degraded the dye by nearly 95% in 120 min of exposure time. The degradation of dye with time was fitted to pseudo-first- order and pseudo-second-order kinetic models where the data best fit the pseudo-first-order kinetic model. Synthesized AgNPs showed moderate anti-microbial activity against four Gram-positive and Gram-negative bacterial strains while they showed perfect activity against two anti-fungal strains.