SrSnO3 Applied in the Reduction of NO by CO: Influence of Transition Metal Doping on the Catalytic Activity

Strontium stannate (SrSnO3) is a perovskite, which has been extensively studied due to its potential technological applications. In this work, SrSnO3 was doped with transition metals (Cu, Fe, Ni) by the modified Pechini method and evaluated in the catalytic reduction of NO with CO. The perovskite structure was obtained as the major phase for all samples. The catalytic activity of SrSnO3 was highly improved by all the dopants, as only 10% of conversion was obtained for SrSnO3, whereas samples with 5% of Cu presented the highest conversions, reaching 100% of NO into N2 and 100% of CO into CO2 at 550 °C. Conversions of 85% of NO into N2 and 90% of CO into CO2 were obtained for Ni doped samples at 600 °C, while 62% of conversion was obtained for Fe-doped samples, for both reactions. These results indicate that Cu is the best dopant, which leads to the greatest NO conversion with a smaller amount of dopant.