First principles study on the adsorption of CO2 and H2O on the K2CO3 (001) surface

► The DFT surface energies of K2CO3 low index planes indicate the (001) surface is most stable. ► H2O adsorbs much stronger than CO2, and their co-adsorption is repulsive on the K2CO3 (001) surface. ► Under pre-combustion conditions, the ab initio thermodynamics coverage of CO2 is extremely small. ► CO2 adsorption on the surface is limited in a wet stream, limiting the rate of bicarbonate formation.