Simultaneous catalytic removal of NOx and diesel soot particulates over La1−xCexNiO3 perovskite oxide catalysts

A series of the La1−xCexNiO3 (0 ⩽ x ⩽ 0.05) perovskite catalysts for simultaneous removal of nitrogen oxides and diesel soot were prepared by the citric acid complexation. The catalysts were characterized by X-ray diffraction, H2 temperature programmed reduction and X-ray photoelectron spectroscopy. The catalytic performances of these catalysts were investigated by the temperature programmed reaction. The results indicated that Ni2+ was the active centers. The partial substitution of Ce for La increased the concentration of Ni2+, enhancing the catalytic activities. The La0.97Ce0.03NiO3 catalyst showed the highest activity. The maximum productivity of N2 and the ignition temperature were 11.8% and 300 °C, respectively.