High performance CuO-CeO2 catalysts for selective oxidation of CO in excess hydrogen: Effect of hydrothermal preparation conditions

High performance CuO-CeO2 catalysts for selective oxidation of CO in excess hydrogen were prepared by a hydrothermal method under different preparation conditions and evaluated for catalytic activities and selectivities. By changing the nCTAB/nCe ratio and hydrothermal aging time, the catalytic activity of the CuO-CeO2 catalysts increased and the operating temperature window, in which the CO conversion was higher than 99%, was widened. XRD results showed no peaks of CuOx species and Cu-Ce-O solid solution were observed. On the other hand, Cu+ species in the CuO-CeO2 catalysts, which was associated with a strong interaction between copper oxide clusters and cerium oxide and could be favorable for improving the selective oxidation performance of CO in excess H2, were detected by H2-TPR and XPS techniques.