Effect of Copper Substitution and Preparation Methods on the LaMnO3±δ Structure and Catalysis of Methane Combustion and CO Oxidation

LaMn1−xCuxO3±δ perovskite oxides (x = 0, 0.2, 0.4, 0.6, 0.8, 1) were prepared by two different methods, the Pechini and sol-gel methods. The catalysts were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray fluorescence spectroscopy, N2 adsorption, and temperature-programmed reduction. Their catalytic activity in the oxidation of methane and CO was evaluated. EDS and SEM results showed that the Pechini samples had more homogeneity and smaller particles (higher specific surface area). The catalytic activity for methane combustion was highest for x = 0.2. In CO oxidation, the oxides with x = 0.2 and x = 0.4 were the most active. The Pechini samples had higher activity and stability than the sol-gel samples.

Graphical abstractLaMn1−xCuxO3±d perovskite oxides (x = 0-1) prepared by the Pechini method show higher surface area and thus higher activity and stability in CO oxidation and CH4 combustion than that by the sol-gel method.Figure optionsDownload full-size imageDownload as PowerPoint slide