A general and inherent strategy to improve the water tolerance of low temperature NH3-SCR catalysts via trace SiO2 deposition

Water tolerance is an important topic for low temperature NH3-SCR, because of the inevitable deactivation of the catalyst in the presence of water. In this work, it was found that by depositing trace SiO2 onto the surface of Mn0.2Ti0.8O2 catalyst, the catalysts displayed enhanced water-tolerance with no compromise of its initial activity. Furthermore, NH3-TPD, H2-TPR, and XPS results indicated that deposition of SiO2 tuned the pore sizes of the catalysts without modifying their chemical properties, and controlled the inherent capillarity property that led to the improved anti-water performance. This result sheds light on the rational design of NH3-SCR catalysts with enhanced water-tolerance.