Graphene oxide–supported magnetic nanostructures as a new effective catalyst for benzimidazole derivative synthesis: a comparative study

In this study, three novel, sustainable graphene oxide–supported magnetic nanocomposites, GO/Fe3O4/Co3O4, GO/Fe3O4/CaO, and GO/Fe3O4/MgO, were synthesized using graphene oxide as a support. These materials were characterized by field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR), Energy Dispersive X-ray spectroscopy (EDX), Brunauer -Emmett- Teller (BET) analyses, Zeta potential analysis and Vibrating Sample Magnetometry (VSM). The results confirmed the successful formation of the nanocomposites and uniform dispersion of metal oxides on the GO Nanosheets surface. BET analysis revealed that the GO/Fe3O4/Co3O4 nanocomposite shows the highest specific surface area among the prepared materials. The catalytic activities of the nanocomposites were evaluated in the synthesis of a 2-phenylbenzimidazole derivative. Notably, GO/Fe3O4/Co3O4 nanocomposite showed higher catalytic performance compared with GO/Fe3O4/CaO, and GO/Fe3O4/MgO nanocomposites, giving high yields under mild reaction conditions. The higher activity is attributed to the synergistic interaction between GO, Fe3O4, and Co3O4, as well as the increased surface area. Furthermore, the catalyst demonstrated good stability and recyclability. This work highlights the potential of GO-based magnetic nanocomposites as efficient and reusable catalysts for benzimidazole synthesis.