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Fe and Co co-doped Mn-Ce/TiO2 (MCT) catalysts were investigated for the simultaneous removal of nitric oxide (NO) and elemental mercury (Hg 0 ) at reaction temperature lower than 200 °C. The catalysts were characterized by Brunauer-Emmett-Teller (BET), temperature program reduction (TPR), scanning electron microscope (SEM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) analysis.The experimental results showed that the co-doped 2Fe4Co-MCT catalyst exhibited better performance for the simultaneous removal of NO and Hg 0 compared to Fe or Co doped catalysts. This could be due to higher BET surface area and better redox property of 2Fe4Co-MCT catalyst. In addition, we propose that chemisorbed O2 played a dominant role in selective catalytic reduction (SCR) of NO while lattice O2 played a key role in Hg 0 oxidation. The results also indicate that the introduction of Fe species enhanced the activity of SCR, whereas the introduction of Co species enhanced the oxidation of Hg 0 . The synergistic effect of Fe and Co species in the 2Fe4Co-MCT catalyst are also suggested to be an important mechanism for simultaneously removing NO and Hg 0 .

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aMn and Ce were loaded on metal-organic frameworks (MOFs) via impregnation and in situ doping methods. The catalytic capacities of the obtained composite materials were evaluated in the selective catalytic reduction (SCR) of NO. The existing form of Mn-Ce in the MOF originates from different doping methods and its effect on the catalytic performance was investigated. Mn-Ce introduced by impregnation was deposited on the surface of the MOF and exhibited high catalytic efficiency of more than 98% from 200 C to 300 C. According to the results of BET, XRD, XPS, and ICP analyses, it was concluded that Mn-Ce introduced via the in situ doping method was inserted in the crystal lattice structure of the MOF, which resulted in an enlarged surface area, low Mn concentration, and poor redox property as compared to that introduced via the impregnated method. By exploring these factors, it was proven that the limited redox ability was the direct reason that resulted in the low activity of the MnCeMOF. Using thermal decomposition, the in situ doped Mn-Ce was liberated from the MnCeMOF crystal lattice and subsequently, exhibited recovered redox properties and catalytic activity. In this study, we proved that different doping methods lead to different forms of Mn-Ce in the MOF, which exhibit different redox properties and thus directly lead to different catalytic performance.