This work studied the reaction of common pollutants on a catalytic surface under oxidizing conditions. CO and naphthalene were used to reduce NO in the presence of oxygen during the transient heating of metal oxide nanoparticles. The latter consisted of a core-shell SmCeO2@TiO2 support with a TiO2 core and a samarium-stabilized CeO2 shell, impregnated with copper and potassium. The addition of potassium simulated the gradual accumulation of an alkali metal during biomass combustion, which can poison the catalyst. The Cu/SmCeO2@TiO2 catalyst achieved the complete conversions of NO, CO and naphthalene at 225, 236 and 255 degrees C, respectively. Even though the inclusion of potassium had the expected negative effect, the K/Cu/SmCeO2@TiO2 catalyst was still able to fully convert NO and CO at 323 and 299 degrees C, respectively, whereas a maximum naphthalene conversion of only 66% was obtained at 350 degrees C.