Enhanced soot combustion through acid-assisted decoration of K on 3DOM LaFeO₃ perovskite

Developing highly efficient perovskite-based catalysts with advanced catalytic activity has long been a challenging task in the catalytic combustion field. In this study, we proposed an innovative strategy to integrate K on the surface of 3DOM LaFeO₃ via an acetic acid-assisted impregnation strategy. The acid treatment was found to enhance the specific surface areas of perovskite, which in turn facilitated the dispersion of potassium. Meanwhile, the generated cation vacancy in the perovskite lattice proposed a synergistic effect with K, which could accelerate the adsorption and activation of the O₂ and NO_x. The resulting acid-assisted impregnation of LaFeO₃ catalyst (K/LaFeO₃-A) exhibited a significantly higher redox ability, NO_x storage capacity, and abundant active oxygen species, which were found to play a crucial role in promoting soot combustion. Among all the samples investigated, the K/LaFeO₃-A catalyst demonstrated remarkable catalytic performance, with a T₅₀ value of 394 °C for soot combustion. Additionally, the potential reaction pathway for soot combustion was proposed through in-situ DRIFT analysis. This study not only provides new insights into the development of efficient, stable, and environmentally friendly catalysts but also offers a new perspective on the rational design and engineering of perovskite catalysts.