The stabilization of adsorbed carbon dioxide by formate on Cu(100)

The adsorption and desorption of CO 2 on copper has recently achieved much attention as it is expected to play an important role in the methanol synthesis and is known to take part in the water-gas-shift reaction as well as in the formate synthesis on copper. The CO 2 interaction with the clean surface is known to be quite weak, 25–30 kJ mol −1 and the CO 2 molecule is lying parallel to the surface. However, when formate is pre-adsorbed, the CO 2 is found to be stabilized by 14 ± 1 kJ mol −1 per monolayer formate. The bonding geometry is also heavily influenced by the formate as a new loss feature in the HREEL spectra suggests that the molecule is bent, breaking the linear symmetry.