NOx storage behavior of BaO in different structural environment in NSR catalysts

Barium oxide containing catalysts with different compositional and structural features have been prepared by impregnation and sol–gel technique for NOx storage reduction (NSR). Barium oxide supported on γ-alumina prepared by impregnation method exhibited better NOx storage reduction behavior compared to the catalysts prepared by sol–gel process. Barium oxide containing ceria/zirconia catalysts were also prepared without alumina, which showed lower NOx storage compared to alumina supported catalysts. In this case also the catalysts prepared by impregnation displayed better NOx storage behavior than the catalyst prepared by sol–gel process. The catalysts were characterized by X-ray diffraction analysis and BET surface area measurements. XRD and BET surface area measurements indicated the influence of structure and composition of the support on the NOx storage behavior of barium oxide.