Malus domestica Mediated Synthesis of Palladium Nanoparticles and Investigation of Their Catalytic Activity Towards the Suzuki Coupling Reactions

Abstract

Synthesis of nanoparticles through green methods is considered to be more eco-friendly and facile as compared to conventional physical and chemical methods. In this work, an environmental friendly method to synthesize palladium nanoparticles (Pd-NPs) by using a fruit extract has been reported. This extract obtained from Malus domestica (apple); acted as a source of reducing agent and functioned as a capping agent as well. The Pd-NPs were monitored and characterized by ultraviolet-visible (UV-Vis) spectroscopy; powder X-rays diffraction (XRD), scanning electron microscopy (SEM) and Fourier-transform infra-red (FT-IR) spectroscopy. FT-IR spectra revealed the presence of abundant amounts of ascorbic acid in the fruit extract which is assumed to reduce the Palladium chloride to Pd-NPs. XRD results confirmed the crystalline nature of Pd-NPs (JCPDS: No. 05-0681, space group: Fm3m (225)). These nanoparticles were further investigated for their catalytic activity towards the Suzuki coupling reactions where by employing only 2 mol% of the catalyst loading these Pd-NPs demonstrated excellent catalytic activity. Progress and completion of reactions were monitored by gas chromatography (GC) while products formed were characterized by gas chromatography-mass spectrometry (GC-MS), FT-IR as well as from their melting points data. Pd-NPs showed excellent catalytic activity; thereby suggesting their potential and scope for various other catalytic transformations.