Perovskite-Like Mixed Oxides (LaSrMn1−x Ni x O4+δ, 0 ≤ x ≤ 1) as Catalyst for Catalytic NO Decomposition: TPD and TPR Studies

Abstract

Catalytic NO decomposition on LaSrMn1−xNixO4+δ (0 ≤ x ≤ 1) is investigated. The activity of NO decomposition increases dramatically after the substitution of Ni for Mn, but decreases when Mn is completely replaced by Ni (x = 1.0). The optimum value is at x = 0.8. These indicate that the catalytic performance of the samples is contributed by the synergistic effect of Mn and Ni. O2-TPD and H2-TPR experiments are carried out to explain the change of activity. The former indicates that only when oxygen vacancy is created, could the catalyst show enhanced activity for NO decomposition; the latter suggests that the best activity is obtained from catalyst with the most matched redox potentials (in this work, the biggest ΔT and ΔE values). The close relationships between activity and ΔT or ΔE indicate that ΔT and ΔE are important parameters of catalyst for NO decomposition.