Synthesis of Nanoparticles Using Lantana Camara and Study of Their Photocatalytic Activity.

Abstract

Nanoscience and nanotechnology have been conquering themselves in the field of research through the future perspective for the modern world. Nanoparticles are one of the fabulous aspects of nanotechnology and nanoscience having at least one dimension in the nanoscale range between 1-100 nm with a very high surface to volume ratio. Considering metallic nanoparticles, silver nanoparticles (AgNPs) are gaining interest day by day because of their broad area of applications in different fields such as pharmaceutical, medicinal, catalysis, and wastewater treatment. Approaching environment-friendly procedures, plant-mediated synthesis is one of the green synthesis methods with less toxicity, easy production, cost-effectiveness, and free from hazardous chemicals. This present study aimed towards the synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract of Lantana camara with silver nitrate (AgNO3) as the precursor. Synthesis of AgNPs was confirmed by a UV-Visible spectrophotometer by observing the Surface Plasmon Resonance (SPR) band peak at 458 nm followed by its color changes from light yellow to dark brown of the reaction media. Fourier Transformed Infrared (FTIR) showed the structure and respective bands of the synthesized nanoparticles and the stretch of bonds. Surface morphology and dispersity were characterized using a Field Emission-Scanning Electron Microscope (FE-SEM) and the particles were observed spherical without agglomeration and the particle size was found approximately in the range between 15 to 35 nm. The purity and crystalline nature of AgNPs were revealed by Energy Dispersive Spectroscopy (EDS) and X-ray Diffraction (XRD) analysis, respectively. Photocatalytic activity of AgNPs was observed against Methylene blue (MB) dye under solar light irradiation. Green synthesized silver nanoparticles effectively degraded the dye by nearly 95% at 5 h of exposure time. The degradation of dye at various concentrations was fitted to Langmuir and Freundlich isotherm models and the data showed best fitting toward Freundlich isotherm model. The degradation of dye with the 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 bacterial strains (gram-positive and gram-negative) while they showed very good activity against two anti-fungal strains.