Competitive Adsorption of CO_2 and H_2O Molecules on the BaO (100) Surface: A First-Principle Study

• Published in: Bulletin of the Korean Chemical Society pp. 988 - 992
• Main Authors: 권순철, 이왕로, Hanna Lee, 김준, 이한림
• Format: Journal Article
• Language: English
• Published: 대한화학회 01.03.2011
• Subjects: 화학
• ISSN: 0253-2964; 1229-5949

CO_2 adsorption on mineral sorbents has a potential to sequester CO_2. This study used a density functional theory (DFT) study of CO_2 adsorption on barium oxide (BaO) in the presence of H_2O to determine the role of H_2O on the CO_2 adsorption properties on the (2 × 2; 11.05 Å × 11.05 Å) BaO (100) surface because BaO shows a high reactivity for CO_2 adsorption and the gas mixture of power plants generally contains CO_2 and H_2O. We investigated the adsorption properties (e.g., adsorption energies and geometries) of a single CO_2 molecule, a single H_2O molecule on the surface to achieve molecular structures and molecular reaction mechanisms. In order to evaluate the coordinative effect of H_2O molecules, this study also carried out the adsorption of a pair of H_2O molecules, which was strongly bounded to neighboring (−1.91 eV) oxygen sites and distant sites (−1.86eV), and two molecules (CO_2 and H_2O), which were also firmly bounded to neighboring sites (−2.32 eV) and distant sites (−2.23 eV). The quantum mechanical calculations show that H_2O molecule does not influence on the chemisorption of CO_2 on the BaO surface, producing a stable carbonate due to the strong interaction between the CO_2 molecule and the BaO surface, resulting from the high charge transfer (−0.76 e). KCI Citation Count: 7