Mechanism of ethanol reforming: Theoretical foundations

Jeng-Han Wang, C. S. Lee, M. C. Lin

研究成果: 雜誌貢獻文章

93 引文 (Scopus)

摘要

The mechanism of ethanol reforming has been systematically studied by both energetic calculation to examine ethanol decomposition and electronic structure analysis to investigate the redox capability of the nine selected metals of Co, Ni, Cu, Rh, Pd, Ag, Ir, Pt, and Au with the same crystal structure and surface orientation. The energetic calculation shows that most of the dissociation barriers are lower on Co(lll), Ni(lll), Rh(lll), and Ir(l 11) surfaces and higher on Cu(l 11), Ag(l 11), and Au(l 11) surfaces. The initial C-H bond dissociation, forming the doubly adsorbed C(H 2 )C(H 2 )O(H) and C(H 2 )C(H 2 )O, with a lower barrier than those in the initial C-C and C-O bond dissociations is considered as the most feasible decomposition route. In addition, the linear correlation between reaction barriers and d-band centers breaks down in the case of C-H bond dissociation due to the lower barriers on Rh(lll) and Ir(lll) surfaces. This result may be related to the suitable bond distances on Rh(lll) and Ir(lll) surfaces to form the more stable double adsorbates, C(H 2 )C(H 2 )O(H) and C(H 2 )C(H 2 )O. In the electronic structure analysis, Rh(lll) and Ir(lll) surfaces with higher density of state (DOS) distributions around the Fermi level can efficiently accept/donate electrons from/to the reacting ethanol and its fragments, showing better redox capability. Therefore, the excellent efficiency of Rh- and Ir-based catalysts, as observed from the reforming experiment, can be attributed to both the lower decomposition barrier and the higher DOS distribution around the Fermi level based on the firstprinciples calculation.

原文英語
頁(從 - 到)6681-6688
頁數8
期刊Journal of Physical Chemistry C
113
發行號16
DOIs
出版狀態已發佈 - 2009 四月 23

指紋

Reforming reactions
Ethanol
ethyl alcohol
dissociation
decomposition
Fermi level
Decomposition
Electronic structure
electronic structure
crystal surfaces
Adsorbates
Crystal orientation
breakdown
routes
fragments
catalysts
Crystal structure
Metals
crystal structure
Catalysts

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films

引用此文

Mechanism of ethanol reforming : Theoretical foundations. / Wang, Jeng-Han; Lee, C. S.; Lin, M. C.

於: Journal of Physical Chemistry C, 卷 113, 編號 16, 23.04.2009, p. 6681-6688.

研究成果: 雜誌貢獻文章

Wang, Jeng-Han ; Lee, C. S. ; Lin, M. C. / Mechanism of ethanol reforming : Theoretical foundations. 於: Journal of Physical Chemistry C. 2009 ; 卷 113, 編號 16. 頁 6681-6688.
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