Leaching inhibition of K species over 3DOM La0.8Sr0.2MnO3 perovskite through CuO embedding: Enhanced stability induced by phase transition for soot elimination

Catalytic combustion is one of the most effective soot elimination technologies, whereby the development of catalyst with high performance and stability becomes the emphasis. Herein, we elaborately fabricated an innovative catalyst of K-Cu decorated 3DOM La0.8Sr0.2MnO3 perovskite called 5KxCLSM for soot combustion, in which Cu species were introduced via redox precipitation method and K species were loaded by impregnation method. The dispersion and interaction between CuO and perovskite were enhanced by this redox precipitation method. CuO could facilitate the phase transition to form K2−xMn8O16, thereby, the free K species were stabilized. However, excessive CuO would cover the active sites and even destroy 3DOM structure. Among all as-prepared catalysts, 5K2CLSM exhibited the best activity with T50 of 357 ℃ and TOF of 2.97 × 10−3 s−1 (320 ℃) and possessed admirable water-resistance and hydrothermal stability. This work rationalizes an approach to develop an active and stable catalyst for soot combustion or other systems. [Display omitted] •3DOM La0.8Sr0.2MnO3 was prepared by colloidal crystal templates method.•CuO species were introduced via redox precipitation method.•The K species were stabilized due to the formation of K2-xMn8O16.•2CKLSM showed high soot combustion activity and stability.