Facile Green Preparation of Rhodium Nanoclusters Supported Nano-Scaled Graphene Platelets for Sonogashira Coupling Reaction and Reduction of p-Nitrophenol

Abstract

Rhodium nanoclusters were uniformly dispersed on nano-scaled graphene platelets by a simple ‘mix and heat’ method without using any toxic reagents. Distilled water was used to obtain the homogenous dispersion of Rh-nanoclusters on graphene platelets. The morphology of the resultant catalyst (Rh(0)NCs/GNPs) was studied by means of transmission electron microscope (TEM) and atomic force microscope (AFM) analyses. The X-ray photoemission spectroscope (XPS) result confirmed the metallic form of Rh-nanoclusters in Rh(0)NCs/GNPs. The crystalline property and the interaction between Rh-nanoclusters and graphene platelets (GNPs) were studied by means of XRD and Raman analysis. The Rh-loading in Rh(0)NCs/GNPs was confirmed by scanning electron microscope and energy dispersive spectroscope (SEM-EDS) and inductively coupled plasma-mass spectroscope (ICP-MS) analysis. After being optimized, the Rh(0)NCs/GNPs used as catalyst for the reduction of 4-nitrophenol with NaBH4 and the Sonogashira coupling reaction between iodobenzene with phenylacetylene. To our delight, the Rh(0)NCs/GNPs showed excellent catalytic activity towards the reduction of 4-nitrophenol with an excellent turnover frequency (TOF) value of 112.5 min−1. The kapp and k’ values were calculated to be 62.07 × 10−3 min−1(0.002 mg of Rh(0)NCs/GNPs) and 31035 × 10−3 mg−1 min−1,respectively. Alike, under the optimal conditions, the Rh(0)NCs/GNPs gave the desired product, diphenylacetylene, in a good yield of 87% with 91% selectivity. The Rh(0)NCs/GNPs can be reused without significant loss in its catalytic activity.

Synthesis and characterization of the ternary graphene oxide, MnFe2O4 nanoparticles, and Polyamidoamine dendrons nanocomposite decorated with palladium as a heterogeneous catalyst for nitroaromatics reduction

“…Given their extraordinary and unique physical, chemical, and mechanical properties as well as their easy functionality, graphene and its derivatives, offer new opportunities for a wide range of applications, especially in catalytic reactions where they are typically used as a support for, or a protector of catalysts and as a catalytic center by itself. [ 8 ] In this respect, graphene and its derivatives have been functionalized with different substances including metal nanoparticles (e.g., Pd, [ 9 ] Pt, [ 10 ] Ag, [ 11 ] Au, [ 12 ] Rh, [ 13 ] Ni, [ 14 ] Cu, [ 15 ] etc. ), [ 16 ] magnetic nanoparticles (e.g., Fe 3 O 4 [ 17 ] or MFe 2 O 4 , where M = Zn, [ 18 ] Co, [ 19 ] Mn, [ 20 ] and Cu [ 21 ] ), metal complexes, [ 22 ] polymers, and different dendrimers [ 23 ] to obtain binary and ternary systems for different applications.…”

Optimized Loading of Carboxymethyl Cellulose (CMC) in Tri-component Electrospun Nanofibers Having Uniform Morphology

“…However, continuous development is key to sustaining a developing society. Nanotechnology is one of the most advanced technologies, which covers a wide range of applications [1][2][3]. Electrospinning is a technique to produce the nonwoven mats that offer a large surface-area-to-mass ratio.…”