Photo-induced strong active component-support interaction enhancing NOx removal performance of CeO2/TiO2

Abstract CeO2 supported TiO2 catalysts exhibit poor low temperature catalytic activities in relative studies and applications for NOx reduction to N2 due to the weaker interaction between CeO2 and TiO2. Herein, novel Ultraviolet (UV) light photo-treatment method was developed for treating CeO2/TiO2 (Ce/Ti) catalyst prepared by conventional wet impregnation. XRD, Raman, XPS, H2-TPR analyses suggested that photo-treatment induced a stronger interaction between CeO2 and TiO2 and high content oxygen vacancies and Ce3+ ions. All these changes significantly improved the redox properties of Ce/Ti catalyst. The catalytic performance test results showed that the photo-treated Ce/Ti catalysts exhibited much higher NO removal efficiency than untreated Ce/Ti and also high stability. Followed promotional mechanism studies via ammonia temperature-programmed desorption (NH3-TPD) and in situ diffuse reflectance infrared spectrometer (DRIFT) proved that the superior selective catalytic reduction (SCR) catalytic activity of photo-treated Ce/Ti catalysts were attributed to the collective effect of higher acidity and better redox properties. We expected that this work would contribute to developing new feasible approach to enhancing the catalytic performance of supported oxide catalyst.