在Pt(111)上非晶态固体水膜界面处电子激发产生分子氢。

Electron-stimulated production of molecular hydrogen at the interfaces of amorphous solid water films on Pt(111).

作者信息

Petrik Nikolay G, Kimmel Greg A

机构信息

Fundamental Sciences Directorate, Pacific Northwest National Laboratory, Mail Stop K8-88, Richland, Washington 99352, USA.

出版信息

J Chem Phys. 2004 Aug 22;121(8):3736-44. doi: 10.1063/1.1773152.

DOI:10.1063/1.1773152

PMID:15303941

Abstract

The electron-stimulated production of molecular hydrogen (D(2), HD, and H(2)) from amorphous solid water (ASW) deposited on Pt(111) is investigated. Experiments with isotopically layered films of H(2)O and D(2)O are used to profile the spatial distribution of the electron-stimulated reactions leading to hydrogen within the water films. The molecular hydrogen yield has two components that have distinct reaction kinetics due to reactions that occur at the ASW/Pt interface and the ASW/vacuum interface, but not in the bulk. However, the molecular hydrogen yield as a function of the ASW film thickness in both pure and isotopically layered films indicates that the energy for the reactions is absorbed in the bulk of the films and electronic excitations migrate to the interfaces where they drive the reactions.

摘要

研究了沉积在Pt(111)上的非晶态固体水(ASW)受电子激发产生分子氢（D₂、HD和H₂）的过程。利用H₂O和D₂O同位素分层薄膜进行实验，以描绘导致水膜内氢气产生的电子激发反应的空间分布。分子氢产率有两个组分，由于在ASW/Pt界面和ASW/真空界面发生的反应（而非在本体中发生的反应），这两个组分具有不同的反应动力学。然而，纯薄膜和同位素分层薄膜中分子氢产率作为ASW薄膜厚度的函数表明，反应能量在薄膜本体中被吸收，并且电子激发迁移到界面，在那里驱动反应。