Ni nanocatalysts supported on mesoporous Al2O3–CeO2 for CO2 methanation at low temperature

The selectivity and activity of a nickel catalyst for the hydrogenation of carbon dioxide to form methane at low temperatures could be enhanced by mesoporous Al₂O₃–CeO₂ synthesized through a one-pot sol–gel method. The performances of the as-prepared Ni/Al₂O₃–CeO₂ catalysts exceeded those of their single Al₂O₃ counterpart giving a conversion of 78% carbon dioxide with 100% selectivity for methane during 100 h testing, without any deactivation, at the low temperature of 320 °C. The influence of CeO₂ doping on the structure of the catalysts, the interactions between the mesoporous support and nickel species, and the reduction behaviors of Ni²⁺ ions were investigated in detail. In this work, the addition of CeO₂ to the composites increased the oxygen vacancies and active metallic nickel sites, and also decreased the size of the nickel particles, thus improving the low temperature catalytic activity and selectivity significantly.

The addition of CeO₂ to form Ni composite catalysts increased the oxygen vacancies and active metallic nickel sites thus improving the low temperature CO₂ methanation performance.