硫醇自主分子薄膜的形成機制

Formation Mechanism of Alkanethiol Self-Assembled Monolayers

10.6623/chem.2002038

陳俊顯(Chun-hsien Chen)；蔡東谷(Tung-Ku Tsai)

自組分子單層膜 ； 掃瞄式穿隧顯微鏡 ； 硫醇 ； self-assembled monolayrs ； SAMs ； scanning tunneling microscope ； STM ； alkanethiols

化學

60卷3期（2002 / 09 / 01）

391 - 397

繁體中文

自組分子單層膜(SAMs，self-assembled monolayers)已廣泛地應用在許多領域的研究，最受矚目、應用最廣的是硫醇分子在金表面形成的SAMs。本文主要敘述Poirier 於Science (1996, 272, 1145)所觀察之硫醇SAMs 形成機制，此研究在高真空條件下進行，並具分子尺寸解析度相當。此外也介紹數篇在溶液相中進行的相關研究之論文。

Self-assembled monolayers (SAMs) of alkanethiols on gold surface have been a popular technique in many aspects of scientific and technical research. Introduced in the review article is the formation mechanism of SAMs observed in ultrahigh vacuum and in diluted alkanethiol solutions by SPM (scanning probe microscope). The mechanism is generalized as two steps. At the initial stage, the alkanethiols appear stripes on gold surface, indicating a lying down orientation for the molecular chain. A first-order Langmuir adsorption isotherm is proposed. After saturation of the striped phase, the monolayer undergoes a phase transition, resulting in a (√3x√3)R30° where the molecular chains align ~30° from surface normal.