The adsorption of oxygen and water on Ca and CaO films studied with MIES, UPS and XPS
The adsorption of oxygen and water on Ca and CaO films studied with MIES, UPS and XPS
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DOI：
10.1016/j.susc.2008.02.011
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发表时间：
2008-05-01
期刊：
影响因子：
1.9
通讯作者：
Maus-Friedrichs, W.
中科院分区：
文献类型：
--
作者：
Bebensee, F.;Voigts, F.;Maus-Friedrichs, W.
利用亚稳态诱导电子能谱（MIES）、紫外光电子能谱（UPS）和X射线光电子能谱（XPS）研究了Ca和CaO薄膜对水的吸附以及Ca薄膜对氧的吸附。在干净的Si（100）衬底上蒸镀Ca膜。CaO膜通过在氧气氛中在400 ℃的衬底温度下蒸发Ca来制备。在室温下的钙膜上的气体吸附，无论是氧气和水，发起的碰撞分子的完全解离，导致形成的Ca-O键。此外，暴露于水导致通过从水中夺取氢而形成羟基，从而形成完整的表面层。在CaO膜暴露于水时也形成羟基，但与暴露于水的Ca膜相比，羟基的量显著更小。(C)2008 Elsevier B. V.保留所有权利。
Metastable induced electron spectroscopy (MIES), Ultraviolet photoelectron spectroscopy (UPS), and X-ray photoelectron spectroscopy (XPS) are employed to study the adsorption of water on Ca and CaO films as well as the adsorption of oxygen on Ca films. Ca films are prepared by evaporation of Ca onto clean Si(l 0 0) substrates. CaO films are produced by Ca evaporation in an oxygen atmosphere at a substrate temperature of 400 degrees C. Gas adsorption on the Ca films at room temperature, both for oxygen and water, is initiated by complete dissociation of the impinging molecules leading to the formation of Ca-O bonds. Exposure to water furthermore leads to the formation of hydroxyl groups via hydrogen abstraction from water forming a complete surface layer. Hydroxyl groups are also formed upon exposure of CaO films to water, but to a significantly smaller amount compared to Ca films exposed to water. (C) 2008 Elsevier B.V. All rights reserved.