Hydrogen penetration and diffusion on Mg17Al12 (110) surface: A density functional theory investigation. (12th October 2017)

• Record Type: Journal Article
• Authors: Zhang, Ziyan; Zhou, Xingyu; Zhang, Hongliang; Guo, Jin; Ning, Hua
• Is Part Of: International journal of hydrogen energy. Volume 42:Number 41(2017)
• Page Start: 26013
• Page End: 26019
• Publication Date: 2017-10-12
• Subjects: Density functional theory -- Hydrogen storage -- Adsorption -- Penetration -- Mg-Al alloy; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2017.08.176
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: The adsorption, diffusion and penetration of H on the Mg17 Al12 (110) surface are investigated systematically by means of the density functional theory calculations. Results indicate that H and H2 prefer to adsorb on the Mg-Mg bridge sites of the Mg17 Al12 (110) surface. The lowest barrier energy of molecular hydrogen dissociation on the (110) surface is ∼0.87 eV. The penetration processes of atomic hydrogen incorporation into the Mg17 Al12 (110) surface are discussed. It is obtained that the H penetrates from the Mg17 Al12 (110) surface into the subsurface with the minimum barrier of ∼0.63 eV, while the hydrogen atom spreads into the deeper Mg17 Al12 (110) surface with lower barrier. Highlights: Adsorption and diffusion of H/H2 on (in) Mg17 Al12 (110) surface are studied. Hydrogen atoms and molecules prefer to adsorb on the Mg-Mg bridge sites. The barrier energy of H2 dissociation on the Mg17 Al12 (110) surface is 0.87 eV. Atomic hydrogen penetrates into the subsurface with the minimum energy of 0.63 eV.