Effect of Addition of Base on Ceria and Reactivity of CuO/CeO_2 Catalysts for Low-Temperature CO Oxidation

摘要

In this work, we have reported the influence of the addition of base (KOH) on the physic-ochemical property of ceria synthesized by alcohothermal process, and the alcohothermal mechanism was also put forward. Furthermore, the prepared CeO_2 was used as the support to prepare CuO/CeO_2 catalysts via the wet impregnation method. The samples were characterized by N2 adsorption-desorption, X-ray powder diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and temperature-programmed reduction by H_2 (H_2-TPR). The catalytic properties of the CuO/CeO_2 catalysts for low-temperature CO oxidation were studied using a microreactor-GC system. The crystal size of CeO_2-A was much smaller than that of CeO_2-B, and the corresponding copper oxide catalysts exhibited higher catalytic activity than that of the Ce02-B-supported catalysts under the same reaction conditions. The alcohothermal mechanism indicated that KOH plays a key role in determining the physicochemical and catalytic properties of ceria-based materials.