Monolithic LaBO 3 (B=Mn, Co or Ni)/Co 3 O 4 /cordierite Catalysts for o ‐Xylene Combustion

Perovskite/perovskite‐like (LaBO 3 , B=Mn, Co or Ni)/Co 3 O 4 with different morphologies were successfully integrated onto the surface of three‐dimensional (3‐D) cordierite honeycomb ceramics by two‐step combination method of hydrothermal synthesis and impregnation for the catalytic combustion of o ‐xylene. The La 2 NiO 4 /Co 3 O 4 composite exhibits a 3D hierarchical hollow microsphere construction assembled by numerous nanowires, which is different from the nanowire structure of LaMnO 3.15 /Co 3 O 4 and LaCoO 3 /Co 3 O 4 . Compared to LaMnO 3.15 /cordierite, Co 3 O 4 /cordierite, LaMnO 3.15 /Co 3 O 4 /cordierite and LaCoO 3 /Co 3 O 4 /cordierite, the La 2 NiO 4 /Co 3 O 4 /cordierite catalyst possesses lower light‐off temperature and better catalytic performance. The higher catalytic activity of La 2 NiO 4 /Co 3 O 4 /cordierite catalyst may be correlated with higher specific surface area, larger oxygen storage and the synergistic effect of the La 2 NiO 4 and Co 3 O 4 . In addition, when the perovskite‐like loading was 11.39 wt% and calcined at 600 °C for 4 hours, it exhibited the best catalytic performance for o ‐xylene oxidation with 90% conversion at 299 °C. In addition, the catalyst also has good conversion stability.