Potassium promoted Fe–Ce composite oxides monolithic catalysts for catalytic soot combustion

In this work, the potassium promoted Fe–Ce composite oxides supported on the monolithic three-dimensional (3D) macroporous nickel foam substrates (KFeCe@NF) were synthesized by sequential wetness impregnation method and used for catalytic soot combustion. The best catalytic performance was obtained over K(0.1)FeCe@NF catalyst under 10%H 2 O/800ppmNO/20%O 2 /N 2 atmosphere using a wet contact mode and the lowest T 10 , T 50 and T 90 values could reduce to 274 ℃, 313 ℃ and 353 ℃, respectively. A detailed comparison of the structural properties for the samples before and after potassium loading was conducted by XRD, FESEM, EDS and XPS. The addition of K could lead to reduction of partial Fe 2 O 3 to FeO and make the Fe 2 O 3 nanosheets transform into agglomerated nanoparticles. Moreover, the enhanced catalytic performance of KFeCe@NF for soot combustion is main due to the abundant active oxygen species inspired by the strong interaction between potassium and transition metal oxides.