Synthesis, structure, and properties of a Au/MnOx–CeO2 nanocatalyst for low-temperature oxidation of carbon monoxide

Resumo

We have synthesized Au/MnO_x–CeO₂ nanocatalysts for the low-temperature oxidation of carbon monoxide. Gold nanoparticles applied by the deposition precipitation (DP) method were used as an active phase. The composition, structure, and textural characteristics of the materials and the charge state of the components of the catalysts were studied using X-ray diffraction, X-ray photoelectron spectroscopy, highresolution transmission electron microscopy, inductively coupled plasma mass spectrometry, and low-temperature nitrogen adsorption measurements. The carbon monoxide concentration in the catalytic oxidation products was determined by gas chromatography. The influence of calcination temperature on the charge state of the components of the surface layer of Au/ MnO_x–CeO₂ and the catalytic activity of the materials was examined. The catalytic activity of the materials was shown to be determined to a significant degree by the Mn³⁺, Au³⁺, and weakly bound oxygen concentrations in the surface layer.