Green Synthesized of Ag/AgO Nanoparticles Using Aqueous Leaves Extracts of L. and Their Azo Dye Photodegradation.

In this study, silver/silver oxide nanoparticles (Ag/AgO NPs) were successfully biosynthesized using L. aqueous leaves extract. The effect of different plant extract/precursor contractions (volume ratio, /%) on Ag/AgO NP formation, their optical properties, and photocatalytic activity towards azo dye degradation, i.e., Congo red (CR) and methylene blue (MB), were investigated. X-ray diffraction confirmed the crystalline nature of Ag/AgO NPs with a crystallite size range from 28 to 39 nm. Scanning electron microscope images showed that the Ag/AgO NPs have an oval and spherical shape. UV-vis spectroscopy showed that Ag/AgO NPs have a direct bandgap of 2.07-2.86 eV and an indirect bandgap of 1.60-1.76 eV. Fourier transform infrared analysis suggests that the synthesized Ag/AgO NPs might be stabilized through the interactions of -OH and C=O groups in the carbohydrates, flavonoids, tannins, and phenolic acids present in L. Interestingly, the prepared Ag/AgO NPs showed high catalytic degradation activity for CR dye. The photocatalytic degradation of the azo dye was monitored spectrophotometrically in a wavelength range of 250-900 nm, and a high decolorization efficiency (84.50%) was obtained after 50 min of reaction. As a result, the use of L. aqueous leaves extract offers a cost-effective and eco-friendly method.