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%H2O/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 celcius, 313 celcius and 353 celcius, 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 Fe2O3 to FeO and make the Fe2O3 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.