Direct decomposition of NO into N2 and O2 on SrFe0.7Mg0.3O3 perovskite oxide

NO direct decomposition on doped SrFeO3 perovskite oxide was investigated. The ability of SrFeO3 for direct decomposition of NO is strongly affected by the dopant in Fe sites. Among the examined dopants and compositions, the highest yield of N-2 was achieved on SrFe0.7Mg0.3O3. When SrFe0.7Mg0.3O3 was loaded with Pt, the N-2 yield further improved, and the light-off temperature fell by 100K. On this catalyst, the yields of N-2 and O-2 were 56 and 35%, respectively, at 1123 K. On the Pt-loaded SrFe0.7Mg0.3O3 catalyst, the NO decomposition rate increased with increase in the NO partial pressure with P-NO(1.31). The presence of oxygen slightly decreased the N-2 yield with P-O2(-0.12). Therefore, the effect of oxygen poisoning on NO decomposition upon Pt-loaded SrFe0.7Mg0.3O3 is small. From the result Of O-2-TPD, Pt loading possibly weakens the adsorption strength of surface oxygen and enhances NO adsorption. In summary, this study shows that the substitution of Fe with lower valence cation in SrFeO3 and also loading a small amount of Pt are highly effective for increasing the NO decomposition activity.