Formation of Adsorbed Layers by Deposition of Dinitrogen Pentoxide, Nitric Acid, and Water on Graphite

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• 作者：Liza S. E. Romero Lejonthun ; Erik A. Svensson ; Patrik U. Andersson ; Jan B. C. Pettersson
• 刊名：Journal of Physical Chemistry C
• 出版年：2009
• 出版时间：May 7, 2009
• 年：2009
• 卷：113
• 期：18
• 页码：7728-7734
• 全文大小：201K
• 年卷期：v.113,no.18(May 7, 2009)
• ISSN：1932-7455

文摘

The formation of adsorbed layers of dinitrogen pentoxide, nitric acid, and water on graphite has been studied by molecular beam and light-scattering techniques. The desorption kinetics of N₂O₅ on graphite were described by the Arrhenius equation with an activation energy of 0.24 ± 0.03 eV and a pre-exponential factor of 2.3 × 10^{(10 ± 0.73)} s⁻¹, and N₂O₅ is concluded to bind more strongly than H₂O to the graphite surface. Elastic helium scattering and light scattering were used to probe the formation of adlayers on the surface. Adsorption of pure N₂O₅ resulted in formation of thin adlayers at temperatures below 160 K. In coadsorption experiments N₂O₅ was concluded to facilitate the formation of thick N₂O₅−H₂O ice layers at 155 K. In a similar way coadsorption of HNO₃ and H₂O resulted in the formation of thick adlayers at 170 K. N₂O₅ and HNO₃ both bind more strongly than water to the graphite surface and are concluded to facilitate nucleation and growth of ice.