Abstract: A series of MnOx–CeO2 and MnOx–TiO2 catalysts were prepar船白ed by a homogeneous precipita見費tion method and their catalytic activ都物ities for the NO oxidation in睡舊 the absence or presence of SO2 were evaluated. Results 跳朋show that the optimal molar低子 ratio of Mn/Ce and Mn/Ti are 0.7 an自土d 0.5, respectively. The MnOx–CeO2 catalyst exhibits hi科唱gher catalytic activit明公y and better resista少見nce to SO2 poisoning than the MnOx–TiO2 catalyst. On the basis of Bru人飛nauer–Emmett–Teller (BET), X-r作些ay diffraction (XRD)技厭, and scanning transmission electr樹林on microscope with mapping (STEM-mappin長街g) analyses, it is s樂體een that the MnOx–CeO2 catalyst possesses higher 飛東BET surface area and better dispersi視離on of MnOx over the catalyst than MnOx–TiO2 catalyst. X-ray photoelectron s店也pectroscopy (XPS) measureme時樹nts reveal that MnOx–CeO2 catalyst provides the a習作bundance of Mn3+ and more surface adso低是rbed oxygen, and SO2 might be preferentially adsorbed t新長o the surface of CeO匠訊2 to form sulfate species, whic拿學h provides a protection of MnOx active sites from being 也們poisoned. In contrast, MnOx active sites over the Mn船場Ox–TiO2 catalyst are easily and quickly 就短sulfated, leading to麗雨 rapid deactivation of如志 the catalyst for NO oxidati用生on. Furthermore, temperature progra也畫mmed desorption with NO 拿嗎and O2 (NO + O2-TPD) and in situ diffuse reflectance i店服nfrared transform spectr現街oscopy (in situ DRIFTS) char房志acterizations results show t機音hat the MnOx–CeO2 catalyst displays much stronger abili森這ty to adsorb NOx than the MnOx–TiO2 catalyst, especially after SO2 poisoning.
