• 文献标题:   Understanding adsorption of hydrogen atoms on graphene
  • 文献类型:   Article
  • 作  者:   CASOLO S, LOVVIK OM, MARTINAZZO R, TANTARDINI GF
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF CHEMICAL PHYSICS
  • ISSN:   0021-9606
  • 通讯作者地址:   Univ Oslo
  • 被引频次:   257
  • DOI:   10.1063/1.3072333
  • 出版年:   2009

▎ 摘  要

Adsorption of hydrogen atoms on a single graphite sheet (graphene) has been investigated by first-principles electronic structure means, employing plane-wave based periodic density functional theory. A 5 X 5 surface unit cell has been adopted to study single and multiple adsorptions of H atoms. Binding and barrier energies for sequential sticking have been computed for a number of configurations involving adsorption on top of carbon atoms. We find that binding energies per atom range from similar to 0.8 to similar to 1.9 eV, with barriers to sticking in the range 0.0-0.15 eV. In addition, depending on the number and location of adsorbed hydrogen atoms, we find that magnetic structures may form in which spin density localizes on a root 3 X root 3R30 degrees sublattice and that binding (barrier) energies for sequential adsorption increase (decrease) linearly with the site-integrated magnetization. These results can be rationalized with the help of the valence-bond resonance theory of planar pi conjugated systems and suggest that preferential sticking due to barrierless adsorption is limited to formation of hydrogen pairs. (c) 2009 American Institute of Physics.