微波加热分解法制备CuO-Ce_(0.6)Zr_(0.4)O_2及其催化CO氧化性能

Preparation of CuO-Ce_(0.6)Zr_(0.4)O_2 by Microwave Heating Decomposition and Its Catalytic Property for CO Oxidation

采用微波加热分解法制备了一系列CuO含量(0-25%,w)不同的CuO-Ce0.6Zr0.4O2催化剂,并用X射线衍射(XRD)、透射电镜(TEM)、N2吸附-脱附(BET)和H2程序升温还原(H2-TPR)技术对催化剂进行了表征,利用色谱流动法考察了其催化CO低温氧化性能.结果表明:当CuO含量为15%时,所制备催化剂的催化活性最佳.在催化剂中存在三种不同类型的铜物种,即高分散、小颗粒和大颗粒的CuO.催化剂表面高分散和小颗粒的CuO有利于催化活性的提高,而大颗粒的CuO对催化活性具有抑制作用.

A series of CuO-Ce0.6Zr0.4O2 catalysts with different contents （0-25%, w） of CuO were prepared by microwave heating decomposition and characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, N2 adsorption-desorption （BET）, and temperature-programmed reduction with hydrogen （H2-TPR）. The activities of the catalysts for CO oxidation were evaluated using a microreactor-gas chromatograph system. The results show that the CuO-Ce0.6Zr0.4O2 catalyst exhibits the best catalytic activity for CO oxidation at a CuO content of 15%. Three copper species are present in the catalysts, i.e., highly dispersed, small and large CuO particles. The highly dispersed and small CuO particles are responsible for the promotion of catalytic activity while the large CuO particles inhibit catalytic activity.