Different iron species exhibit distinct activity and selectivity in CO₂ hydrogenation reaction. Herein, by controlling calcination temperature, Fe-Al interaction in Na promoted Fe-Al catalysts has been regulated, which further leads to various compositions of iron oxide (FeO_x) and iron carbides (Fe₇C₃ and Fe₅C₂) after CO activation and CO₂ hydrogenation reaction. The phase compositions and structures of Fe-Al catalysts are carefully distinguished by multiple characterizations, including XRD, XPS, MES and TEM, and the reactivity of different phases is studied with the combination of experiments (kinetics, TP and in situ DRIFTS) and Density Functional Theory (DFT) calculations. Our FeAl350 with the highest FeC_x content shows the highest CO₂ conversion of 48.2% and the lowest CO selectivity of 10.1%, and FeAl900 with the highest Fe₅C₂ / FeC_x ratio presents the highest C₅₊ selectivity of 44.6%. Finally, a correlation between different compositions of iron species with the activity and selectivity of Fe-based for CO₂ hydrogenation to olefins was established.

_{不同的铁物种在CO 2}加氢反应中表现出不同的活性和选择性。在此，通过控制煅烧温度，可以调节 Na 促进的 Fe-Al 催化剂中的 Fe-Al 相互作用，进而导致氧化铁 (FeO _x ) 和碳化铁 (Fe ₇ C ₃和 Fe ₅ C ₂ )的不同组成。 CO活化和CO ₂加氢反应。通过 XRD、XPS、MES 和 TEM 等多种表征仔细区分 Fe-Al 催化剂的相组成和结构，并结合实验（动力学、TP 和原位）研究不同相的反应性漂移）和密度泛函理论（DFT）计算。我们的 FeC _x含量最高的 FeAl350 的 CO ₂转化率最高，为 48.2%，CO 选择性最低，为 10.1%，而 Fe ₅ C ₂ / FeC _x比率最高的 FeAl900 的 C ₅₊选择性最高，为 44.6%。最后，建立了不同铁组分组成与铁基CO ₂加氢制烯烃的活性和选择性之间的相关性。