| In this work, a series of Cu-X mixed oxides catalysts with the Cu/X molar ratio of1:1were prepared by the hydrothermal method and their catalytic activities for the decomposition of N2O have been investigated. Cu-Ce mixed oxides catalyst was found to be actve for the decomposition of N2O. Furthermore, the molar ratio of Cu/Ce affects its activity and the optimum ratio is1:1. Meanwhile, the given results reveals that the best calcination temperature is500℃. Based on the Characterization(XRD, BET, H2-TPR, SEM), it was found that the addition of CeO2can not only promote the surface area of CuO, but also improve the reducing capacity of Cu2+to Cu+thus leading to the high catalytic performance. In addition, K showed a promoting effect on the activity of CuCeOx and the optimal amount of K is1wt.%. The addition of CTAB during the catalyst preparation resulted in more active CuCeOx obtained due to the increased surface area and the decreased particle size as characterized by N2adsorption and SEM.Considering that Co3O4showed the preferable activity in a series of Cu-X mixed oxides catalysts, we prepared a series of Co-Ce mixed oxides catalysts with different Cu/X molar ratios by the hydrothermal method. Activity measurements showed that Co-Ce mixed oxide with the molar ratio of Co:Ce was1:0.1was the most active. It was found that the reducing capacity from Co3+to Co2+plays a key role for the catalytic performance.Finally, Co3O4nano particles with different morphologies (spherical-like, rod-like, plate-like and flower-like) were prepared by the different methods to investigate the effect of morphology on the catalytic activity of Co3O4for the decomposition of N2O. The plate-like Co3O4catalyst showed the highest activity among the prepared Co3O4catalysts. The activity decreased in the order of plate-like>flower-like>spherical-like> rod-like. HRTEM revealed that different morphology leads to different crystal plane exposed, which is closely related to the catatlytic performance of Co3O4catalyst. |
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