Electronic properties and catalytic performance for DME combustion of lanthanum manganites with partial B-site substitution.

The effect on the geometric, electronic, and catalytic properties of LaMnO 3 oxides of replacement of 50% Mn with Cr, Fe, Co, and Ni in combustion reactions of dimethyl ether has been studied. The similarity in the ionic radius does not produce larger differences in the geometric properties of the compounds, whereas the differences in the stability of their cation valences produce significant changes in their electronic properties. The high stability of Cr 3+ and Fe 3+ species does not increase the Mn 4+ /Mn 3+ redox pair ratio in LaMn 0.5 Cr 0.5 O 3 and LaMn 0.5 Fe 0.5 O 3 . Meanwhile, the high stability of Co 2+ and Ni 2+ species favors the oxidation of Mn 3+ to Mn 4+ and the mobility of anionic oxygen in the LaMn 0.5 Co 0.5 O 3 and LaMn 0.5 Ni 0.5 O 3 catalysts, which improves their catalytic performance. [ABSTRACT FROM AUTHOR]