Electron paramagnetic resonance analysis of La(1-x)M(x)MnO(3+d) (M=Ce, Sr) perovskite-like nanostructured catalysts

The physical-chemical properties of some nanostructured perovskite-like catalysts of general formula La 1-xM xMnO 3+δ (M = Ce, Sr) have been investigated, in particular by using the electron paramagnetic resonance (EPR) technique. We show that the interplay between the -O-Mn 3+-O-Mn 4+-O- electron double-exchange and the electron mobility is strictly dependent on the dopant nature and the annealing conditions in air. A relationship between the observed properties of these samples and their activity in the methane flameless catalytic combustion is proposed.