Two-Step Approach to the Formation of Organic Monolayers on the Silicon Oxide Surface
Two-Step Approach to the Formation of Organic Monolayers on the Silicon Oxide Surface
复制标题
在二氧化硅表面形成有机单层的两步法
作者：
Ryan C. Major and;X. Zhu
开发了一种新的合成策略，用于在氧化物表面形成致密堆积的单分子膜。这项技术包括一个简单的两步过程，在这个过程中，氧化物表面最初被氯化，然后暴露在酒精分子中，通过Si−O键形成单分子层。我们通过在氧化终止的Si(111)表面上形成十八醇(C18)单分子膜来证明这一方法。结合多种技术对所得C18H37O−单分子膜进行表征，发现其为部分无序的致密堆积薄膜。在最高的表面覆盖率下，薄膜的厚度被确定为24A。在低覆盖率下，单层生长的动力学特征是一个快速的初始步骤；当表面覆盖率接近饱和时，速率常数下降3个数量级。
A new synthetic strategy has been developed for the formation of densely packed monolayers on oxide surfaces. This technique involves a simple two-step procedure in which the oxide surface is initially chlorinated and then exposed to alcohol molecules for monolayer formation via Si−O linkages. We demonstrate this approach with the formation of octadecanol (C18) monolayers on the oxide-terminated Si(111) surface. Characterization of the resulting C18H37O− monolayer by a combination of techniques reveals a densely packed film with partial disorder. At the highest surface coverage, the thickness of the film is determined to be 24 A. Kinetics of monolayer growth is characterized by a fast initial step at low coverage; the rate constant decreases by 3 orders of magnitude when surface coverage approaches saturation.