Green synthesis of palladium nanoparticles using gum ghatti (Anogeissus latifolia) and its application as an antioxidant and catalyst

A facile and green route for the synthesis of palladium nanoparticles from palladium chloride was developed using non-toxic, renewable plant polymer, gum ghatti (Anogeissus latifolia), as both the reducing and stabilizing agent. The generated nanoparticles were characterized with UV–visible spectroscopy (UV–vis), dynamic light scattering (DLS), transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. The formation of palladium nanoparticles was confirmed from the appearance of intense brown colour and broad continuous absorption spectra in the UV–visible region. The produced nanoparticles were found to be spherical in shape, polydisperse and the average particle size was 4.8 ± 1.6 nm. The face centred cubic crystal structure of the fabricated nanoparticles is confirmed from the selected-area electron diffraction and XRD patterns. Compared to earlier reports, the nanoparticles showed superior antioxidant at a much lower nanoparticle dose. Also, the homogenous catalytic activity of palladium nanoparticles was studied by probing the reduction of dyes such as coomassie brilliant blue G-250, methylene blue, methyl orange, and a nitro compound, 4-nitrophenol with sodium borohydride. The nanoparticles exhibited excellent catalytic activity in dye degradation and the results of this study demonstrate the possible application of biogenic palladium nanoparticles as nanocatalyst in environmental remediation. Keywords: Antioxidant, Catalyst, Green synthesis, Gum ghatti, Palladium nanoparticles, Dye degradation