Structure-performance relationship between denitration performance and catalytic interface morphologies of MnCeO /P84 catalytic filters

MnCeO/P84 catalytic filters with spherical, flower-like, cubic and rod-like catalytic interfaces were synthesized respectively, and their catalytic activities in the NH3-SCR reaction were investigated. The MnCeO/P84 catalytic filter with spherical catalytic interfaces (recorded as S-MnCeO/P84) exhibits the best catalytic denitration performance. The NO removal efficiency of S-MnCeO/P84 reaches the highest value of 98.6% at 160 °C when the catalyst loading is 100 g/m2. At the same time, S-MnCeO/P84 exhibits good SO2 resistance and stability, achieving a NO removal rate of 83% at 190 °C with 30 ppm SO2. The characterization results illustrate that the MnCeO active component in S-MnCeO/P84 is present in weak crystalline states, tightly wrapped around the surface of the filter fiber, and uniformly dispersed, and the mesopore is the main pore structure of the S-MnCeO/P84, which can provide a channel for the catalytic reaction to proceed. At the same time, transmission electron microscopy (TEM) characterization shows that γ-MnO2 is the main form of MnO2 in the S-MnCeO/P84. Further analysis of H2 temperature programmed reduction (H2-TPR), NH3 temperature programmed desorption (NH3-TPD) and in-situ diffuse reflectance infrared spectra (DRIFTS) show that S-MnCeO/P84 has good redox ability at 100–200 °C and has abundant Lewis acid sites and Brønsteds acid sites, which provides an important guarantee for its superior low-temperature NH3-SCR denitration performance.