Co nanoparticles anchoring three dimensional graphene lattice as bifunctional catalyst for low-temperature CO oxidation

Abstract

Despite tremendous efforts, developing a series of heterogeneous catalysts for CO oxidation elimination with high activity at low cost remains a great challenge. Here, we report a bifunctional Co-based nanocrystals anchoring in the graphene oxide layer as a high-performance catalyst for CO oxidation. Although a single cobalt or graphene oxide catalysts alone have the lower catalytic activity, their combination exhibits an unexpected, surprisingly high CO activity that is further enhanced by a series of oxygen-containing functional groups on the surface of graphene oxide sheets. The Co/graphene oxide calcined at 300°C (Co/GO–300°C) exhibits the outstanding catalytic activity with T100=51°C but superior stability, producing a high-performance non-precious metal-based catalyst for CO oxidation elimination. Under a series of critical characterizations, the unusual catalytic activity of Co/GO–300°C sample is attributed to the synergistic effect between the oxygen-containing functional groups of graphene oxide sheets and Co species. Especially, the existence of Co3+ species could promote the adsorption and activation of CO molecules.