MOFs-Derived Fe–Co Bimetallic Catalyst for Selective CO₂ Hydrogenation to Light Olefins

The catalysis of CO2 to light olefins (C2=–C4=) utilizing Fe–Co bimetallic catalysts is deemed a practicable approach to counteract the excessive emission of CO2. However, a significant research gap exists in the study of manipulating the interaction between Fe–Co alloys, particularly in terms of component control. In this work, a range of bimetallic catalysts with varying Co/Fe molar ratios supported on ZrO2 were obtained through pyrolysis of mixed metal organic framework NH2-MIL-88B(Fe/Co)@UiO-66 that enables the hydrogenation of CO2 to C2=–C4=. Notably, the catalyst 10Fe1Co@ZrO2 exhibited a C2=–C4= selectivity of 45% at a CO2 conversion of 44.6%. The characterization results authenticate that, compared to the bare Fe catalyst, introducing Co significantly enhances the CO2 adsorption and conversion. Intriguingly, CoFe2O4 formed in both 10Fe1Co@ZrO2 and 5Fe1Co@ZrO2 undergoes reduction to generate CoxFey, facilitating its subsequent carbonization into the active phase χ-(CoxFe1–x)5C2 more readily during the reaction process.