Interactive CO2Adsorption on the BaO (100) Surface: A Density Functional Theory (DFT) Study

A density functional theory (DFT) study of CO₂ adsorption on barium oxide (BaO) adsorbents is conducted to understand the chemical activity of the oxygen site on the BaO (100) surface. This study evaluated the adsorption energies and geometries of a single CO₂ molecule and a pair of CO₂ molecules on the BaO (100) surface. A quantum calculation was performed to obtain information on the molecular structures and molecular reaction mechanisms; the results of the calculation indicated that CO₂ was adsorbed on BaO to form a stable surface carbonate with strong chemisorption. To study the interactive CO₂ adsorption on the BaO (100) surface, a pair of CO₂ molecules was bound to neighboring and distant oxygen sites. The interactive CO₂ adsorption on the BaO surface was found to slightly weaken the adsorption energy, owing to the interaction between CO₂ molecules.