Adsorption of CO₂ on Transition Metal-Doped Cu Clusters: A DFT Study

Activation of CO2 is the first step towards its reduction to more useful chemicals. Electrochemical CO2 reduction reactions can lead to high value-added chemical and materials production while helping decrease anthropogenic CO2 emissions. In studies, it was found that copper metal clusters can reduce CO2 to more than thirty different hydrocarbons and oxygenates, yet they lack the required selectivity. Density functional theory (DFT)-based studies are carried out on copper clusters, doped clusters, nano-structures and Cu-based alloy catalysts to assess the activity and selectivity of CO2 reduction to generate carbon monoxide (CO), formic acid (HCOOH), formaldehyde (H2C=O), methanol (CH3OH) and methane (CH4 ). In this chapter, we will discuss the effect of the adsorption of CO2 on (Sc, Ti, V) metaldoped clusters. DFT studies carried out for these clusters showed a high CO2 adsorption energy, a low activation barrier for its dissociation, and a facile regeneration of the clusters. The reaction energies (dopant-dependent), the mechanisms for reaction, dissociation barriers for CO2, and less desorption energies (dopant dependent) for carbon monoxide (CO) during the activation of CO2 with Cu3X clusters (X= first row transition metals) are discussed in the chapter. C6Li6 is not capable of capturing CO2 molecules but is effective in their storage. The interaction of CO2with superalkalis such as FLi2 , OLi3 , and NLi4 and non-metallic superalkalis such as F2H3 , O2H5, and N2H7 is also included due to its applications.