Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (1): 16802-016802.doi: 10.1088/1674-1056/22/1/016802

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Methane adsorption on graphite(0001) films: a first-principles study

何满潮, 赵健   

  1. State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Beijing 100083, China
  • 收稿日期:2012-05-29 修回日期:2012-07-09 出版日期:2012-12-01 发布日期:2012-12-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 40972196 and 41172263).

Methane adsorption on graphite(0001) films: a first-principles study

He Man-Chao (何满潮), Zhao Jian (赵健)   

  1. State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Beijing 100083, China
  • Received:2012-05-29 Revised:2012-07-09 Online:2012-12-01 Published:2012-12-01
  • Contact: Zhao Jian E-mail:zhaojian0209@yahoo.com.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 40972196 and 41172263).

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摘要： Using first-principles methods, we have systematically investigated the electronic density of states, work function, and adsorption energy of the methane molecule adsorbed on graphite(0001) films. The surface energy and the interlayer relaxation of the clean graphite(0001) as a function of the thickness of the film were also studied. The results showed that the interlayer relaxation is small due to the weak interaction between the neighboring layers. The one-fold top site is found most favourable on substrate for methane with the adsorption energy of -133 meV. For the adsorption with different adsorption heights above the graphite film with four layers, the methane is found to prefer to appear at about 3.21 mÅ above the graphite. We also noted that the adsorption energy does not dependent much on the thickness of the graphite films. The work function is enhanced slightly by adsorption of methane due to the slight charge transfer from the graphite surface to the methane molecule.

关键词: first-principles calculations, graphite, methane molecule, adsorption

Abstract: Using first-principles methods, we have systematically investigated the electronic density of states, work function, and adsorption energy of the methane molecule adsorbed on graphite(0001) films. The surface energy and the interlayer relaxation of the clean graphite(0001) as a function of the thickness of the film were also studied. The results showed that the interlayer relaxation is small due to the weak interaction between the neighboring layers. The one-fold top site is found most favourable on substrate for methane with the adsorption energy of -133 meV. For the adsorption with different adsorption heights above the graphite film with four layers, the methane is found to prefer to appear at about 3.21 mÅ above the graphite. We also noted that the adsorption energy does not dependent much on the thickness of the graphite films. The work function is enhanced slightly by adsorption of methane due to the slight charge transfer from the graphite surface to the methane molecule.

Key words: first-principles calculations, graphite, methane molecule, adsorption

中图分类号:  (Ab initio calculations of adsorbate structure and reactions)

  • 68.43.Bc
68.43.Fg (Adsorbate structure (binding sites, geometry)) 73.20.At (Surface states, band structure, electron density of states) 73.30.+y (Surface double layers, Schottky barriers, and work functions)