Efficient and Stable Co/β-Mo2C Catalyst for Hydroformylation

The hydroformylation of olefins is one of the most important industrial processes used for aldehyde synthesis, which commonly involves the use of scarce and expensive rhodium-based catalysts. It is therefore important to develop inexpensive catalysts, e.g., cobalt-based catalysts with sufficiently high activity and stability for hydroformylation. However, conventional metallic Co clusters, acting as active centers, suffer from low activity and severe metal leaching. Here, we show that Mo6C2-bonded Co can serve as an efficient active center for propene hydroformylation, with a total turnover number of 3158 after five in situ cycles, which is approximately 7.5 times higher than that of conventional metallic Co clusters. Furthermore, the developed Co6Mo6C2 catalyst effectively suppresses cobalt leaching, demonstrating its stability in a long-lasting test. The results of theoretical calculations and characterization analyses demonstrate that the enhanced activity and stability of Mo6C2-bonded Co result from a reduction in the overall energy barrier for hydroformylation and the stability of the Co6Mo6C2 crystal structure, which originates from the strong interaction between Co and the support.