| Summary: | A novel sodium-promoted Fe-Co/NC catalyst prepared by incipient-wet-impregnation method using ZIF-67 as a support was employed to convert CO<sub>2</sub> to light olefins through hydrogenation reaction. Properties of the synthesized catalysts calcinated at various temperatures (from 400 to 700 °C) were investigated by XRD, SEM, TEM and Mӧssbauer spectroscopy. Characterization results showed that the support could be fully converted into carbon support above 500 °C, which could anchor metal particles, thus resulting in a uniform dispersion of active components. Furthermore, the Fe-Co alloy was formed during N<sub>2</sub> calcination, and was converted into active components, such as Fe<sub>3</sub>O<sub>4</sub>, Fe<sub>5</sub>C<sub>2</sub>, and Co<sub>2</sub>C during the reaction. The reaction result indicated that FeCo/NC-600 catalyst exhibited the highest selectivity of light olefins (C<sub>2</sub>= − C<sub>4</sub>=, 27%) and CO<sub>2</sub> conversion could reach around 37% when this catalyst pyrolyzed at 600 °C in N<sub>2</sub>. The highest selectivity for light olefins may be related to the combination of suitable particle size and sufficient active sites of iron carbide.
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