Isotopic Transient Kinetic Study of N2O Decomposition on LaMnO3+δ
Journal of Molecular Catalysis A: Chemical
||Isotope exchange kinetics, LaMnO3, N2O decomposition, Oxygen diffusion
Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences, Pr. Acad. Lavrentieva 5, Novosibirsk 630090, Russia
Novosibirsk State University, Str. Pirogova 2, Novosibirsk 630090, Russia
Analysis of label oxygen transfer during the reaction of N2O decomposition (18O2/N216O) on LaMnO3 + δ indicated that 16O transfer from N216O to 16O2 preceded faster compared to oxygen exchange 18O2/16O2 and involved the interaction with two lattice oxygen of perovskite. It suggests that surface oxygen vacancies play an important role in reactivity of LaMnO3 and explains why at times correlation can be found between catalytic activity and bulk oxygen diffusion (La1 - xSrxMnO3 ± δ) and at other time catalytic properties correlate with surface oxygen exchange constant (La1-xSrxFeO3-θ). The former can be due to general correspondence between surface oxygen exchange kinetics and bulk oxygen diffusion.