Carbon Supports and Promoters: Key to Design Copper Catalysts for CO2 Conversion

Abstract

The impact that greenhouse gases, such as CO2, on Earth's climate is more visible than ever. Converting such a harmful gas into useful commodity chemicals, represents a valuable strategy to tackle global warming. Methanol and syngas (carbon monoxide and hydrogen mixture) are widely used to produce chemicals and fuels. Nowadays, they derived from natural gas and coal. Alternatively, they can be produced using CO2. However, economic and technological obstacles must be overcome. One being the design of suitable catalysts. A catalyst is a substance that speeds up a certain chemical reaction. The focus of this thesis was the study of copper-based catalysts for CO2 conversion to produce methanol and syngas. The chemical reaction takes place at the surface of the metal. Therefore, to maximize the exposed metal surface area, the metal shaped in nanoparticles is deposited on a support. Here, we reported how both the copper nanoparticles size and the type of support used affect the obtained products and the catalyst efficiency. A strategy to enhance the catalysts performance is to add metal oxide promoters. Here we covered the role of several promoters for methanol and syngas production. Advanced characterization techniques (i.e. X-ray absorption spectroscopy) allowed us to get insight into the nature of the copper-promoter interaction. These findings provide guidelines for the rational design of copper catalysts for CO2 conversion to produce chemicals and fuels.