Efficient reduction of Graphene oxide to Graphene Nanosheets by Silica based Ionic Liquid: Synthesis, Characterization and Catalytic properties of IMD-Si/FeCl4ˉ@GNS
The aim of the present protocol is to develop a facile route for the synthesis of novel ionic liquid (IL) functionalized graphene nano sheets (IMD-Si/FeCl4ˉ@GNS). An imidazolium IL with iron chloride as an anion (IMD-Si/FeCl4ˉ) was used to reduce graphene oxide. IMD-Si/FeCl4ˉ@GNS was well characterized by various techniques such as Fourier Transform Infrared (FTIR), Raman, Ultraviolet-Visible Diffuse Reflectance Spectroscopy (UV-VIS DRS), Scanning Electron Microscope/Energy Dispersive X-ray (SEM/EDX), Elemental mapping, Transmission Electron Microscope (TEM), Powder X-ray diffraction (XRD), Thermal Gravimetric (TG), Electron Paramagnetic Resonance (EPR), and X-Ray Photoelectron Spectroscopy (XPS) analyses. The IL functionalized material was investigated for its catalytic property and found to be an efficient catalyst for the synthesis of (E)-selective substituted thiosemicarbazone derivatives. The (E)-selectivity was confirmed by the DFT calculations which showed that the (E)-isomer was stabilized by 4.90 kcal/mol more than the (Z)-isomer. The catalyst maintained its catalytic activity for six successive runs.