During the catalyst synthesis process, the precursor chosen could have great impact on the physiochemical and surface properties of the catalysts. More importantly, the precursor could result in very different catalytic activities of the catalyst. In this work, two series of FeO_x/CeO₂ catalysts were prepared using iron nitrate/sulfate precursors with a wide range of Fe loading (1 wt% – 30 wt%). The catalytic activity, physical property, surface morphology and surface/molecular structure were investigated using GC, BET, XRD, Raman, FT-IR as well as SEM and EDS techniques. From the results, although the physical properties (specific surface area, total pore volume) of the catalyst were similar with different precursors, the surface composition and molecular structures were very different. The iron nitrate precursor fully transformed into FeO_x after the calcination process, whereas the iron sulfate precursor only partially transformed into FeO_x, leaving some FeSO₄ on the catalyst surface. The catalytic activity results suggested that a near monolayer coverage of FeO_x on the catalyst surface was crucial to increase the catalytic activity in the NO reduction by CO reaction, while the presence of FeSO₄ had advert impacts on the catalytic activity.

在催化剂合成过程中，选择的前体可能会对催化剂的物理化学和表面性能产生重大影响。更重要的是，前体可能导致催化剂的催化活性截然不同。在这项工作中，FeO _x / CeO _2的两个系列催化剂是使用硝酸铁/硫酸铁前体制备的，这些前驱体具有广泛的铁载量（1 wt％– 30 wt％）。使用GC，BET，XRD，Raman，FT-IR以及SEM和EDS技术研究了催化活性，物理性质，表面形态和表面/分子结构。从结果可以看出，尽管不同的前体催化剂的物理性质（比表​​面积，总孔体积）相似，但其表面组成和分子结构却大不相同。煅烧过程后，硝酸铁前体完全转化为FeO _x，而硫酸铁前体仅部分转化为FeO _x，剩下一些FeSO ₄在催化剂表面上。催化活性结果表明，FeO _x在催化剂表面上的近单层覆盖对于提高CO还原NO的催化活性至关重要，而FeSO ₄的存在会对催化活性产生不利影响。