The hydrogenation of carbon dioxide to olefins (CTO) represents an ideal pathway towards carbon neutrality. However, most current CTO catalysts require a high-temperature condition of 300-450°C, resulting in high energy consumption and possible aggregation among active sites. Herein, we developed an efficient iron-based catalyst modified with high-sodium content (7%) and low-cobalt content (2%), achieving a CO2 conversion of 22.0% and an olefin selectivity of 55.9% at 240°C and 1000 mL/g/h, and it is even active at 180°C and 4000 mL/g/h with more than 25% olefins in hydrocarbons. The catalyst was kept stable under continuous operating conditions of 500 hours. Numerous characterizations and calculations reveal high content of sodium as an electronic promoter enhances the stability of the active anorthic Fe5C2 phase at low temperatures. Further incorporating the above catalyst with cobalt, as a structural promoter, causes Fe species to form a FexCoy alloying phase, which in turn facilitates the formation of higher active anorthic (FexCoy)5C2 phase, different from the conventional carbides and alloy carbides. An in-depth investigation of the synergistic effects of structural and electronic promoters can improve catalyst performance, increase reaction efficiency and cost-effectiveness, and provide profound insights for understanding and optimizing CO2 hydrogenation reactions.

中文翻译：

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低温 CO2 加氢制烯烃在惰性 NaCoFe 合金碳化物上


二氧化碳加氢制烯烃 （CTO） 是实现碳中和的理想途径。然而，目前的大多数 CTO 催化剂需要 300-450°C 的高温条件，导致高能耗并可能在活性位点之间聚集。在此，我们开发了一种高钠含量 （7%） 和低钴含量 （2%） 改性的高效铁基催化剂，在 240°C 和 1000 mL/g/h 下实现了 22.0% 的 CO2 转化率和 55.9% 的烯烃选择性，它甚至在 180°C 和 4000 mL/g/h 下具有活性，碳氢化合物中烯烃含量超过 25%。催化剂在 500 小时的连续操作条件下保持稳定。大量表征和计算表明，高含量的钠作为电子促进剂增强了活性北离子 Fe5C2 相在低温下的稳定性。将上述催化剂进一步与钴结合，作为结构促进剂，使 Fe 物种形成 FexCoy 合金相，这反过来又促进了与传统碳化物和合金碳化物不同的更高活性无极性 （FexCoy）5C2 相的形成。深入研究结构和电子促进剂的协同效应可以改善催化剂性能，提高反应效率和成本效益，并为理解和优化 CO2 加氢反应提供深刻的见解。