Anatase TiO₂ (TiO₂-A), TiO₂-B, and TiO₂-B/anatase mixed-phase TiO₂ (TiO₂-AB) are synthesized, and then utilized as supports for the preparation of Mn-Ce/TiO₂-A, Mn-Ce/TiO₂-B and Mn-Ce/TiO₂-AB, respectively. These catalysts are investigated by various characterizations to understand different phase effect of TiO₂ on physicochemical properties and catalytic activities for ozonation of NO_x into HNO₃, aiming to improve the total NO_x removal efficiency during the subsequent wet absorption process. Characterizations reveal that the catalytic performances follow the order of Mn-Ce/TiO₂-AB > Mn-Ce/TiO₂-B > Mn-Ce/TiO₂-A, which is relevant to the surface -OH content, oxygen vacancy amount, and reducibility property. The surface -OH groups participate in the transformation of O₃ into reactive oxygen species (ROS), the oxygen vacancies increase the activity of surface -OH for ROS generation, and the superior reducibility property accelerates the cycling of Ce³⁺ → Ce⁴⁺ → Ce³⁺ reaction. Moreover, OH and HO₂ radicals are identified as the main reactive species involved in the ozonation of NO_x into HNO₃. Especially, Mn-Ce/TiO₂-AB presents the best catalytic performance mainly because of the optimal reducibility property.

合成了锐钛矿型TiO ₂（TiO ₂ -A），TiO ₂ -B和TiO ₂ -B /锐钛矿混合相TiO ₂（TiO ₂ -AB），然后用作制备Mn-Ce / TiO的载体₂ -A，Mn-Ce / TiO ₂ -B和Mn-Ce / TiO ₂ -AB。通过各种表征对这些催化剂进行了研究，以了解TiO ₂对NOx的物理化学性质和催化活性的不同相作用，以将NO _x臭氧化为HNO ₃，目的是改善总NO _x在随后的湿吸收过程中的去除效率。表征表明，催化性能遵循Mn-Ce / TiO ₂ -AB> Mn-Ce / TiO ₂ -B> Mn-Ce / TiO ₂ -A的顺序，这与表面-OH含量，氧空位量有关以及可还原性属性。表面-OH基团参与O ₃向活性氧（ROS）的转化，氧空位增加了表面-OH生成ROS的活性，并且优异的还原性加速了Ce ³⁺ →Ce ⁴⁺的循环→Ce ³⁺反应。此外，OH和HO ₂ 自由基被确定为将NO _x臭氧化为HNO ₃的主要反应物种。尤其是，Mn-Ce / TiO ₂ -AB表现出最佳的催化性能，这主要是由于其最佳的还原性。