Epoxidation of trans-stilbene with molecular oxygen over an eco-friendly heterogeneous cobalt oxide/reduced graphene oxide composite material

Abstract

We report the synthesis of 1, 5, 10 wt% cobalt oxide/reduced graphene oxide (CoO–RGO) composite materials by a simple solvothermal method. We assessed their catalytic activity in liquid phase epoxidation reaction without any sacrificial reductant and fully characterised the prepared catalysts by different techniques, including powder XRD, Raman spectra, scanning electron microscopy, transmission electron microscopy and ICP-MS. 5 wt% Cobalt oxide (CoO–RGO-5) promoted material showed high conversion (57%) of trans-stilbene oxide and excellent selectivity (96%) towards trans-stilbene epoxidation in DMF solvent by using the molecular oxygen as an oxidant. The conversion efficiency of trans-stilbene reaction remained the same for fresh and recycled catalysts after the 4th run.