Structure and catalytic behaviour of CuO-CeO2 prepared by high-energy ball milling

The aim of this study is to prepare CuO-CeO2 composite by means of mechanical milling and to investigate its characteristics as a catalyst. The structural and morphological features of milled samples are observed by X-ray diffractometry and scanning electron microscopy. The redox property and total OSC (oxygen storage capacity) of the milled sample were measured by using GC-TCD and TG-DTA, which are important parameters to indicate the effectiveness of catalysts. Interestingly, reduction of CuO is repeatedly observed when milling of CuO-CeO2 powder mixture is processed in air. The redox property of milled CuO-CeO2 sample is investigated by H-2-TPR, where three reduction peaks are observed for 0 h milling and only one broad peak for various other milling times. The total OSC of mechanically driven CuO-CeO2 catalyst is much higher than that of the CeO2-ZrO2 traditional catalyst system at low temperatures.