Cu／CeO2纳米催化剂的制备及性能

The Preparation and Catalytic Properties of Cu/CeO_2 Nano-catalysts

采用热解硝酸铈法制备出一系列CeO2纳米粉体,进一步采用浸渍、还原法制备了Cu/CeO2纳米催化剂,运用UV-Vis、FT-Raman、XRD、TEM及微反-色谱装置对样品进行了结构表征和催化CO氧化性能研究.结果表明,热解温度影响CeO2的结构和Cu物种在其上的分散情况,随着热解温度的升高,CeO2粒度逐渐增大,结构有序性逐渐增强,而粒度形貌趋向多样性,同时Cu物种在其上的分散性变差;Cu/CeO2催化剂表现出较高的催化活性,且其活性远远高于单纯的Cu和CeO2.

CeO2 nano-particles with different physical properties are prepared by thermal decomposition of cerous nitrate. Then, the prepared CeO2 are used as supports for Cu/CeO2 catalysts prepared via impregnation combined with deoxidation method. The samples are characterized by UVVis, FT-Raman, XRD and TEM. The catalytic properties of the Cu/CeO2 catalysts for low-temperature CO oxidation are studied by using a microreactor-GC system. The results show that thermal decomposition temperatures affect the structure of the CeO2 particles. When the calcination temperature is lower than 600 ℃, it has little effect on the catalytic activity. However, heat- ing the sample at high temperatures （e. g. 800 ℃） before deoxidation process results in a significant impact on the catalytic activity because of CeO2 crystal growth and Cu aggregation.