Green synthesis of highly dispersed Cu metal nanoparticles catalysts

Abstract

Biosynthesis process offers highly dispersed and stable Cu NPs catalysts (Cu NPs average size of 1.6 nm and 1.8 nm). Bionanotechnology approach for metal nanoparticles ( NPs ) synthesis is cost-effective and environmentally friendly. Organic molecules present in plant extracts can be efficiently utilized for bio-reduction of metal ions into metal NPs in a one-step green synthesis methodology. The biosynthesis procedure for metal NPs synthesis is quick, easy to scale up and can be perform at ambient conditions. The present investigations propose the biosynthesis of highly dispersed and stable copper NPs ( Cu NPs ) supported on NaY zeolite using plant extract of Tinospora cardifolia and Andrographis paniculata for the first time. The structural and morphological attributes of Cu NPs were explored by adopting various physico-chemical techniques, for example Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES), X-ray diffraction (XRD), Temperature Programmed Desorption (CO 2 -TPD and NH 3 -TPD), Temperature Programmed Reduction (H 2 -TPR), N 2 sorption, Electron Microscopy (SEM, TEM and HR-TEM), X-ray Photoelectron Spectroscopy (XPS), etc. The experimental study (XRD, SEM, TEM, and HR-TEM) recommend that the green synthesis method by using plant extract has promising effect for the synthesis of nano-sized, stable and homogeneously dispersed Cu NPs catalysts ( Cu NPs average size of 1.6 and 1.8 nm) as compared to chemical synthesis approach. The present result is better than those of many state-of-the art techniques reported for green synthesis of Cu NPs using plant extract. According to the study, it is advantageous to prepare highly dispersed metal NPs with desired size, shape, morphology and the required properties by using plant extract.