Mn/Co Redox Cycle Promoted Catalytic Performance of Mesoporous SiO2-Confined Highly Dispersed LaMnxCo_(1-x)O3 Perovskite Oxides in n-Butylamine Combustion

摘要

In this study,highly-dispersed perovskite-type oxides LaMnxCo1-xO3 supported on mesoporous SiO2(LMxC_(1-x)O/SiO2)were synthesized by a citric acid-assisted deposition method.For LMxC_(1-x)O/SiO2 catalysts,the double B-site transition metal ions can not only significantly arise the surface defects,but also lead to the formation of(Mn~(3+)+Co~(3+))/(Co~(2+)+Mn~(4+))redox cycle,both of which were able to improve the catalytic performance of LMxC_(1-x)O/SiO2 in n-butylamine combustion.Strikingly,LM_(0.2)C_(0.8)O/SiO2 catalyst showed the optimum catalytic performance(T_(90%)=210℃ at a space velocity of 15,000 mLg_(cat)~(-1)h~(-1))and the lowest NOx yield among the LMxC1-xO/SiO2 samples,which could be greatly assigned to the accelerated activation and circulation of the oxygen species initiated by the surface defects and redox cycle.