Abstract: A series of做窗 MnOx–CeO2 and MnOx–TiO2 catalysts were prepared by a homogeneou門我s precipitation method and th影女eir catalytic activitie門不s for the NO oxidation in the雜機 absence or presence of S員呢O2 were evaluated. Results show that the o媽街ptimal molar ratio of Mn/Ce and 人票Mn/Ti are 0.7 and 0.5湖可, respectively. The MnOx–CeO2 catalyst exhibits higher catalytic a海上ctivity and better resistance to SO購我2 poisoning than the MnOx–TiO2 catalyst. On the basis of B答議runauer–Emmett–Teller (BET), X-ray diff算街raction (XRD), and scan要光ning transmission electron microscop男鐵e with mapping (STEM-mappi通冷ng) analyses, it is s厭好een that the MnOx–CeO2 catalyst possesses higher BET surfac舊水e area and better dispersi木說on of MnOx over the catalyst than MnOx–TiO2 catalyst. X-ray photoele拿司ctron spectroscopy (XP人廠S) measurements reveal 購但that MnOx–CeO2 catalyst provides the abundan些行ce of Mn3+ and more surface adsor鐘很bed oxygen, and SO2 might be preferentially adsor近坐bed to the surface of C東村eO2 to form sulfate specie得金s, which provides a 月光protection of MnOx active sites from being poison車木ed. In contrast, MnOx active sites over the MnOx–TiO2 catalyst are easily an這日d quickly sulfated, leading 土什to rapid deactivation of the catalyst 畫山for NO oxidation. Furthermore, tempe腦如rature programmed desorption with N他動O and O2 (NO + O2-TPD) and in situ diffuse re拍有flectance infrared transform離用 spectroscopy (in situ DRIFTS) 遠西characterizations results show 可新that the MnOx–CeO2 catalyst displays much stronger abili書亮ty to adsorb NOx than the MnOx–TiO2 catalyst, especially after SO2 poisoning.
