Biosynthesis of Ag/almond shell nanocomposite as a cost-effective and efficient catalyst for degradation of 4-nitrophenol and organic dyes

Silver nanoparticles have been immobilized on the surface of waste almond shell using Ruta graveolens sleeves extract as a reducing and stabilizing agent in the present work. FT-IR spectroscopy, photoluminescence spectroscopy, X-ray diffraction (XRD) patterns, field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM) were used to characterize the almond shell supported silver nanoparticles. The diameters of AgNPs on the almond shell were mostly in the 5-15 nm range. The catalytic performance of the synthesized catalysts was studied in reduction of 4-nitrophenol (4-NP), rhodamine B (RhB) and methylene blue (MB) at ambient temperature. AgNPs/almond shell was found to be a highly active and recyclable catalyst in the related reaction, which can be recovered and reused seven times with no appreciable loss of catalytic activity.