Sheet-Like Morphology CuO/Co3O4 Nanocomposites for Enhanced Catalysis in Hydrogenation of CO2 to Methanol

The selective hydrogenation of CO2into high-value chemicals is an effective approach to address environmental issues. Cobalt-based catalysts have significant potential in CO2hydrogenation reaction systems; however, there is a need to control their selectivity better. In this study, copper is introduced onto Co3O4nanosheets using the ion exchange reverse loading method. The unique interaction of these materials significantly alters the selectivity of the cobalt-based catalyst. Results from scanning transmission electron microscopy and scanning electron microscopy indicate that this catalyst enables a more even dispersion of copper species in the Co3O4nanosheets. Temperature-programmed reduction and X-ray photoelectron spectroscopy reveal that the catalyst facilitates the metal–metal interaction between Co and Cu. Temperature-programmed desorption experiments for CO2and H2demonstrate that the close interaction between Co and Cu modifies CO2adsorption, leading to differences in catalytic activity. Moreover, the catalyst effectively suppresses CO2methanation and promotes methanol formation by altering the alkalinity of the catalyst surface and weakening the hydrogen dissociation ability.Keywords:CO2hydrogenation;methanol;cobalt;copper