Mesoporous Ce_0.8Zr_0.2O₂ solid solutions-supported CuO nanocatalysts for CO oxidation: a comparative study of preparation methods

Ce_0.8Zr_0.2O₂ solid solutions were prepared by three different methods, namely, surfactant-assisted, co-precipitation, and sol–gel methods, and were used as supports of CuO nanocatalysts by the deposition-precipitation (DP) method. The prepared supports and catalysts were characterized by using XRD, N₂ adsorption, TEM, and H₂-TPR techniques. The influence of preparation methods on the low-temperature carbon monoxide oxidation activity of these CuO/Ce_0.8Zr_0.2O₂ catalysts was investigated comparatively by using a microreactor-GC system. The catalyst prepared by surfactant-assisted method is more active for low-temperature CO oxidation than the ones prepared by the co-precipitation and sol–gel methods. The support and catalysts prepared by surfactant-assisted method possess mesoporous framework, nanoscale particle size, and high surface area, improving the synergistic effect between CuO species and support, which is beneficial for enhancing the catalytic performance of low-temperature CO oxidation.