Conversion of CO₂ into fuels via solar energy would be a promising strategy to reduce CO₂ emissions and produce value-added carbon compounds. However, the development of efficient light-harvesting and photocatalytic systems remains a significant challenge because of scarcity of low-cost and high-efficiency catalysts in CO₂ conversion. Herein, a tunable selectivity in photothermal CO₂ conversion was demonstrated over a series of Fe-based catalysts developed through a simple hydrogenation/carbonization treatment with commercial Fe₃O₄ as a precursor. The Fe₃O₄ catalyst demonstrated a full selectivity toward CO (about 100%) and 11.3 mmol g^–1 h^–1 activity for the photothermal catalytic conversion of CO₂. More importantly, the pure-phase θ-Fe₃C produced remarkably high selectivity toward hydrocarbon products (>97%) and superior activity (10.9 mmol g^–1 h^–1) in the photothermal conversion of CO₂. Meanwhile, it is found that the selectivity toward a hydrocarbon (CH_x) can be modulated by the extent of hydrogenation/carbonization of the Fe₃O₄ precursor. In addition, we demonstrated the vital influence of the nonthermal effect on the enhanced catalytic performance with the Fe-based catalysts during the photothermal conversion of CO₂.

中文翻译：

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铁基催化剂对CO _2的光热转化和可调节的选择性：从氧化物到碳化物

通过太阳能将CO ₂转化为燃料将是减少CO ₂排放并产生增值碳化合物的有前途的战略。然而，由于在CO ₂转化中缺乏低成本和高效催化剂，有效的光收集和光催化系统的开发仍然是重大挑战。在本文中，证明了通过一系列的以商业上的Fe ₃ O ₄为前体的简单加氢/碳化处理而开发的铁基催化剂，在光热CO ₂转化中具有可调的选择性。铁₃ O ₄催化剂表现出对CO的完全选择性（约100％）和对CO ₂的光热催化转化的11.3 mmol g ^–1 h ^–1活性。更重要的是，纯相位θ-的Fe ₃ C制作朝向烃产物（> 97％）和优异的活性（10.9毫摩尔克显着高的选择性^-1 ħ ^-1中CO的光热转换）₂。同时，发现可以通过Fe ₃ O ₄的氢化/碳化程度来调节对烃（CH _x）的选择性。前体。此外，我们证明了在CO ₂的光热转化过程中，非热效应对铁基催化剂增强催化性能的重要影响。