Catalytic performance of NO oxidation over LaMeO3 (Me = Mn, Fe, Co) perovskite prepared by the sol–gel method

• The sol–gel method is appropriate for the single phase of LaMeO3 (Me = Mn, Fe, Co) perovskite.
• LaCoO3 exhibited the highest activity for NO oxidation reaction.
• After hydrothermal ageing, the crystallite size increased and surface area decreased drastically.
• The active oxygen and adsorbed NO species play key role in the NO oxidation reaction.

The catalytic performance of LaMeO3 (Me = Mn, Fe, Co) perovskite prepared by a sol–gel method was studied. These catalysts were characterized by X-ray diffraction (XRD), N2 adsorption (BET), H2 temperature programmed reduction (TPR), NO temperature programmed desorption (TPD) and CO–O2 pulse. LaCoO3 exhibited the best activity than that of LaFeO3 and LaMnO3 even after hydrothermal ageing. The activity sequence is in accordance with the reducibility of the samples. The activated oxygen species and adsorbed NO play key roles in the NO oxidation reaction.