Co-adsorption of O2 and H2O on Al(111) surface: a vdW-DFT study. Issue 83 (22nd August 2016)

• Record Type: Journal Article
• Authors: Wei, Xin; Dong, Chaofang; Chen, Zhanghua; Xiao, Kui; Li, Xiaogang
• Is Part Of: RSC advances. Volume 6:Issue 83(2016)
• Page Start: 79836
• Page End: 79843
• Publication Date: 2016-08-22
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra17054d
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Using first-principles calculations based on van der Waals density functional theory, we systematically studied the co-adsorption behavior of H2 O and O2 on Al(111) surfaces. Abstract : Using first-principles calculations based on van der Waals density functional theory, we systematically studied the co-adsorption behavior of H2 O and O2 on Al(111) surfaces. The study consists of two parts: (i) the adsorption of H2 O molecules on O pre-adsorbed Al(111) surfaces, and (ii) co-adsorption of H2 O and O2 molecules on a clean Al(111) surface. H2 O adsorbs on O pre-adsorbed Al(111) surfaces in the form of a molecule, while both the adsorption energies and partial density states results prove that the adsorption of H2 O is strengthened with the increasing pre-adsorbed O coverage. An Al atom bonded with H2 O is pulled out of the surface in all adsorbed structures because of the repulsion between pre-adsorbed O atoms and the O atoms of H2 O. For the co-adsorption of H2 O and O2 on a clean Al(111) surface, H2 O molecules can dissociate into OH and H when both of the two O atoms of O2 can interact with H atoms of H2 O, or else they will adsorb on the surface keeping the behavior of single adsorption. For the dissociation adsorption of H2 O, the redistribution of charge occurs and the value of charge transfer from the surface and O2 to H2 O is much larger than that of molecular adsorption, which is larger than 0.1.