Fig. 2: Comparison of the difficulty of adsorbing and activating CO2, H2O molecules, H atom, and forming VO on TiO2 surfaces before and after MxOy decorating.

a Energy barriers (Eads) for activating CO2, H2O molecules, and H atoms to CO2*, H2O*, and H*, respectively, on different surface sites. b Formation energy of VO on corresponding surfaces.