Effect of BaO on Catalytic Activity of Pt-Rh TWC

The effects of BaO doping on the three-way catalytic activity of Pt-Rh catalyst and on water-gas shift were investigated. The results show that the light-off temperatures of hydrocarbon and carbon monoxide and nitrogen oxides of the fresh catalysts slightly differ from those of the aged catalysts, and the catalysts containing CeO2-ZrO2BaO have lower light-off temperature and better catalytic activity than these containing BaO and CeO2-ZrO2 after hydrothermal aging for 5 h at 1000 °C. The catalysts were characterized by means of the temperature-programmed reduction (TPR) in hydrogen and the temperature-programmed desorption (TPD) in oxygen. It is confirmed that the suggested route of CeO2-ZrO2-BaO by coprecipitation can improve the catalytic activity of catalysts.