CO₂ Capture and Conversion on Rutile TiO₂(110) in the Water Environment: Insight by First-Principles Calculations

The conversion of CO₂ by the virtue of sunlight has the great potential to produce useful fuels or valuable chemicals while decreasing CO₂ emission from the traditional fossil fuels. Here, we use the first-principles calculations combined with the periodic continuum solvation model (PCSM) to explore the adsorption and reactivity of CO₂ on rutile TiO₂(110) in the water environment. The results exhibit that both adsorption structures and reactivity of CO₂ are greatly affected by water coadsorption on rutile TiO₂(110). In particular, the solvation effect can change the most stable adsorption configuration of CO₂ and H₂O on rutile TiO₂(110). In addition, the detailed conversion mechanism of CO₂ reduction is further explored in the water environment. The results reveal that the solvation effect cannot only greatly decrease the energy barrier of CO₂ reduction but also affect the selectivity of the reaction processes. These results presented here show the importance of the aqueous solution, which should be helpful to understand the detailed reaction processes of photocatalysts.