Graphene oxide supported molybdenum cluster: first heterogenized homogeneous catalyst for the synthesis of dimethylcarbonate from CO2 and methanol.

The octahedral molybdenum cluster-based compound, Cs2 Mo6 Br(i) 8 Br(a) 6 was immobilized on graphene oxide (GO) by using a facile approach. High resolution transmission electron microscopy results revealed that molybdenum clusters were uniformly distributed on the GO nanosheets. Cs2 Mo6 Br(i) 8 Br(a) 6 was attached to the GO support via chemical interaction between apical ligands of Mo6 Br(i) 8 Br(a) 6 cluster units and oxygen functionalities of GO, as revealed by XPS studies. The developed material was used for the synthesis of dimethyl carbonate by reduction of carbon dioxide. The synthesized catalyst, that is, GO-Cs2 Mo6 Br(i) 8 Br(a) x , exhibited higher catalytic efficiency than its homogeneous analogue without using dehydrating agent. The catalyst was found to be efficiently recyclable without significant loss of catalytic activity.