Directly Converting Syngas to Linear α-Olefins over Core-Shell Fe₃O₄@MnO₂ Catalysts

Converting syngas to value-added chemicals via Fischer-Tropsch synthesis has attracted much attention, whereas the direct hydrogenation of CO to heavy olefins, especially linear α-olefins (LAOs), remains a challenge. In this study, we designed a core-shell Fe₃O₄@MnO₂ catalyst to realize the direct conversion of syngas to LAOs with high efficiency. This catalyst exhibited a high selectivity of 79.60% for total alkenes and 64.95% for C₄⁺ alkenes, 91% of which are LAOs, at a CO conversion of approximately 75%. Promotion of the electron transfer from MnO₂ to Fe₃O₄ inside the core-shell Fe₃O₄@MnO₂ catalyst facilitated the dissociative adsorption of CO molecules on Fe₃O₄ and the spillover of H atoms onto the MnO₂, which enhanced C-C coupling, weakened the hydrogenation activity of the catalyst, and improved the production of LAOs. A superior stability over 100 h was observed, demonstrating the promising potential of this catalyst for industrial applications.