曲阜师范大学颜廷江团队解析了光催化CO₂加氢过程中氧化铁的结构演变及实际活性成分。相关研究成果发表在2024年5月21日出版的《结构化学》。

光催化CO₂加氢反应可以为工业生产高附加值化学品，解决二氧化碳排放过多造成的环境问题。氧化铁由于其不同的结构和合适的带隙而通常用于光催化反应。然而，很少研究光催化CO₂加氢反应过程中的结构演变和真正的活性成分。

该文从普鲁士蓝前驱体中衍生出多种氧化铁，包括α-Fe₂O₃、γ-Fe₂O₃，Fe₃O₄和FeO，以研究其CO₂加氢性能、结构演变和活性成分。特别是，典型的α-Fe₂O₃和γ-Fe₂O₃在反应过程中转化为Fe₃O₄，而Fe/Fe_xO_y在结构上保持稳定。同时，证实了Fe₃O₄是CO生产的主要活性成分，碳氢化合物（CH₄和C₂-C₄）的形成高度依赖于Fe/Fe_xO_y异质结。在最佳催化剂（FeFe-550）上，由于其合适的金属/氧化物组分分布，CO、CH₄和C₂-C₄烃的最佳产率分别为4mmol·g^-1·h^-1、350μmol·g^-1·h^-1和150μmol·g^-1·h^-1。

该项工作考察了不同氧化铁催化剂在光催化CO₂加氢反应中的结构演变，确定了活性成分，揭示了成分与产物之间的关系，并为CO₂的有效利用提供了有价值的见解。

附：英文原文

Title: Deciphering the structural evolution and real active ingredients of iron oxides in photocatalytic CO2 hydrogenation

Author: Mengjun Zhao, Yuhao Guo, Na Li, Tingjiang Yan

Issue&Volume: 2024-05-21

Abstract: Photocatalytic CO2 hydrogenation reactions can produce high-value-added chemicals for industry, solving the environmental problems caused by excessive CO2 emissions. Iron oxides are commonly used in photocatalytic reactions due to their various structures and suitable band gaps. Nevertheless, the structural evolution and real active components during photocatalytic CO2 hydrogenation reaction are rarely studied. Herein, a variety of iron oxides including α-Fe2O3, γ-Fe2O3, Fe3O4, and FeO, were derived from Prussian blue precursors to investigate the CO2 hydrogenation performance, structural evolution and active components. Especially, the typical α-Fe2O3 and γ-Fe2O3 are converted to Fe3O4 during the reaction, while Fe/FexOy remains structurally stable. Meanwhile, it confirmed that Fe3O4 is the main active component for CO production and the formation of hydrocarbons (CH4 and C2-C4) are highly dependent on the Fe/FexOy heterojunctions. The optimal yields of CO, CH4 and C2-C4 hydrocarbons over the best catalyst (FeFe-550) can achieve 4 mmol·g-1·h-1, 350 μmol·g-1·h-1 and 150 μmol·g-1·h-1, respectively, due to its suitable metal/oxide component distribution. This work examines the structural evolution of different iron oxide catalysts in the photocatalytic CO2 hydrogenation reaction, identifies the active components as well as reveals the relationship between components and the products, and offers valuable insights into the efficient utilization of CO2.

DOI: 10.1016/j.cjsc.2024.100348

Source: http://cjsc.ac.cn/cms/issues/629