The Synergistic Effect of CuZnCeOx in Controlling the Formation of Methanol and CO from CO2 Hydrogenation

Abstract

AbstractCO2 hydrogenation will be essential for a sustainable society if methanol and CO can be efficiently obtained using appropriate catalysts. In this paper, a highly efficient CuZnCeOx catalyst was synthesized using a parallel flow coprecipitation method, and was evaluated in CO2 hydrogenation to produce methanol and CO. Interestingly, the catalyst shows excellent activity and stability, and the selectivity of the products can be controlled by the amount of CeOx. Characterization results show that a significant synergistic effect between Cu and metal oxides (ZnO and/or CeOx) was observed at the composite catalysts. Cu plays a critical role in the activation of H2, and CeOx strongly adsorbs CO2. CeOx improved the dispersion of Cu nanoparticles and promoted the spillover of atomic hydrogen, which was beneficial to the generation of methanol. Meanwhile, ZnO exhibited weak adsorption ability for CO2, which was beneficial for the generation of CO. In addition, ZnO can significantly improve the dispersion of the CeOx nanoparticles. Both the dispersion of active sites and the activation abilities of CO2 are critical for catalyst activity and product selectivity. Thus, the ternary catalyst CuZnCeOx shows higher performance than the binary catalysts (CuZnOx and CuCeOx) in the CO2 hydrogenation reaction. This paper provides a viable way to produce selectively methanol or CO from CO2 hydrogenation.