Evaluation of functionalized reduced graphene oxide upgraded with gold nanoparticles as a hybrid nanocatalyst for the solvent-free oxidation of cyclohexene by molecular oxygen
Neda Seyedi, Mohaddesesh Shahabi Nejad, Kazem Saidi, Hassan Sheibani
Abstract
In the present study, the allylic oxidation of cyclohexene is investigated using molecular oxygen as an oxidant under environment-friendly conditions in the presence of rGO-dithiooxamide/Au hybrid nanocatalyst (rGO <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>=</mml:mo> </mml:math> reduced graphene oxide). This hybrid catalyst comprises nanometric spherical gold particles supported on dithiooxamide-functionalized rGO. The structure of the prepared hybrid catalyst was characterized using FT-IR, XRD, SEM and TEM techniques. The catalytic activity results were found to be dependent on pressure, the amount of hybrid nanocatalyst, reaction time, and temperature. In addition, an 85% conversion and 85% selectivity to 2-cyclohexene-1-one were obtained under optimized reaction conditions. The catalytic activity over a recycled catalyst (rGO-dithiooxamide/Au) remained at a satisfactory state after at least five cycles.