Cu/CeO2 Catalyst for Water‐Gas Shift Reaction: Effect of CeO2 Pretreatment

Abstract CuO/CeO 2 is a kind of promising catalysts for the water‐gas shift (WGS) reaction. Efforts were put in to improve its performance through modification of CeO 2 support. In this study, portions of CeO 2 prepared by a co‐precipitation method were separately annealed at 300 °C in air, under vacuum and with H 2 , and were used as supports for the fabrication of CuO/CeO 2 catalysts. The physicochemical properties of the catalysts were characterized by X‐ray diffraction, N 2 ‐physisorption, inductively coupled plasma, Raman spectroscopy, CO 2 temperature‐programmed desorption, and H 2 temperature‐programmed reduction techniques. The relation between catalytic performances and physicochemical properties of the CuO/CeO 2 catalysts were discussed. Among the three catalysts, the one with CuO supported on H 2 ‐reduced CeO 2 shows the highest catalytic activity, mainly due to strong CuO‐CeO 2 synergetic interaction and high concentration of Frenkel‐type oxygen vacancies. The superior catalytic activities can also be attributed to the Cu 0 crystals of small size and the oxygen vacancies in non‐stoichiometric CeO 2‐ x .