摘要
The manganese-cerium complex oxide catalysts were prepared by coprecipitation.The crystal structures,the desorption properties of surface oxygen and reducibility of these catalysts were investigated by means of X-ray diffraction analysis (XRD),temperature-programmed desopotion-mass spectrography (TPD-MS) and temperature-programmed reduction (TPR).The crystal structure of Mn-O and Mn-Ce-O catalysts are bixbyite-Mn2O3 and γ-Mn2O3 respectively.The presence of CeO2 can not change the position of the feature peaks of Mn2O3 on the TPD or profiles,but can increase evidently the amount of the adsorbed surface oxygen,which are correlated with the catalytic activity for methanol oxidation.The activity of the catalyst is optimum when Mn/Ce atom ratio is 4:1.The presence of CeO2 brings a change of the reducibility,which reveals that there is an interaction between Mn2O3 and CeO2.
The manganese-cerium complex oxide catalysts were prepared by coprecipitation.The crystal structures,the desorption properties of surface oxygen and reducibility of these catalysts were investigated by means of X-ray diffraction analysis (XRD),temperature-programmed desopotion-mass spectrography (TPD-MS) and temperature-programmed reduction (TPR).The crystal structure of Mn-O and Mn-Ce-O catalysts are bixbyite-Mn2O3 and γ-Mn2O3 respectively.The presence of CeO2 can not change the position of the feature peaks of Mn2O3 on the TPD or profiles,but can increase evidently the amount of the adsorbed surface oxygen,which are correlated with the catalytic activity for methanol oxidation.The activity of the catalyst is optimum when Mn/Ce atom ratio is 4:1.The presence of CeO2 brings a change of the reducibility,which reveals that there is an interaction between Mn2O3 and CeO2.