Microwaves-assisted synthesis of La1−xAgxMnO3+δ (0 ≤ x ≤ 0.2) perovskites with high surface area: Application to catalytic combustion of methane

ABSTRACT Lanthanum-manganese based perovskites were prepared, both at atmospheric pressure (MW) and at higher pressure (MWHyd), under microwaves irradiation. Structural and physico-chemical properties of the catalysts were investigated using X ray diffraction, X-ray photoelectron spectroscopy (XPS), BET-sorption, and temperature programmed reduction-, or desorption coupled with mass spectrometry, (TPR-MS or TPD-MS). While MW and MWHyd catalysts exhibited the same XRD patterns indexed as pure perovskite structure, their surface physico-chemical properties were found to be strongly influenced by the preparation procedure. The influence of the nature of oxygen species, their amount and their mobility, evidenced by temperature programmed experiments, on the catalytic properties in catalytic combustion of methane in the presence and in the absence H 2 S has been studied.