氧化铁作为铁基费托合成主催化剂的前驱体,其还原活化过程对催化剂整体性能有着至关重要的影响.α-Fe2O3作为一种晶体材料,其暴露晶面对铁基催化剂的还原和活化过程有重要影响,但目前对此仍然缺乏必要的研究.本研究合成了六角片、立方体和菱面体三种不同形貌的α-Fe2O3单晶纳米颗粒,其对应主暴露面分别为(001)、(102)和(104)晶面,然后利用原位拉曼光谱(ORS)研究了CO还原过程中α-Fe2O3晶体结构的转变过程.结果发现,与(104)和(102)晶面相比,(001)晶面具有更好的还原活性.对于三种晶面上的CO吸附和CO2脱附,SEM、TEM和XPS等表征以及DFT理论计算结果表明,CO2脱附是还原过程的决速步骤;(001)晶面对氧原子的束缚能力较弱,导致了其表面CO2更容易脱附,从而促进了整个还原过程.“,”For the Fe-based catalysts in Fischer-Tropsch synthesis, the reduction and activation process of α-Fe2O3 precursor has a significant effect on the catalytic performance. As a crystalline material, the reduction and activation of α-Fe2O3 is assuredly influenced by the exposed crystal plane; however, there is a lack of necessary research in this regard. In this work,α-Fe2O3 nanocrystals of three different morphologies, viz., pseudo-cubic, hexagonal-plate and rhombohedra, were synthesized, which mainly expose the crystal planes of (102), (001) and (104), respectively. The evolution of α-Fe2O3 crystal structure was then investigated in CO atmosphere by using the Operando Raman spectroscopy (ORS). The results show that the α-Fe2O3 (001) plane has a better reductive activity in comparison to the (104) and (102) planes. The SEM, TEM, XPS and XRD characterization and DFT calculation results reveal that CO2 desorption is a decisive step for the reduction of α-Fe2O3;owing to the weak binding ability of (001) crystal plane to oxygen atoms, the desorption of CO2 on the (001) crystal plane is much easier, which can promote the reduction process.