本研究利用電化學式掃描電子穿隧顯微鏡(Electrochemical Scanning Tunneling Microscopy, EC-STM)與循環伏安儀(Cyclic Voltammetry, CV)來探討3,4-ethylenedioxythiophene(EDOT)分子由磷酸鹽緩衝溶液(phosphate buffer solution, PBS)吸附至Au(111)電極表面的自組裝行為，及其單分子膜在表面上的電化學聚合現象。研究結果發現EDOT單體可以在Au(111)表面進行氧化吸附，形成具有(4×5), (3×2√13), (3×7) 及 (5×√3)等多種結構的單分子膜。其起始吸附電位約為-0.25V (v.s Pt)，並在更負的電位(-0.4 V)進行脫附。當施加較低的電位進行吸附時，分子能緩慢地自組裝至表面上，因此形成更規則有序的單分子膜。
在高分子化的過程中需施加大於0.2 V的電壓才能進行聚合反應。然而，當電極持續施予一恆定的電壓時，除了單分子膜以外溶液中的單體也同樣能參與聚合反應，導致於電極表面聚合而成的高分子膜形成多層結構；相反地，當施加於電極的電壓以循環掃描(-0.25 V – 0.25 V) 的方式進行調控，藉由來回間斷的終止/進行單體聚合來控制反應逐層的進行，因此能獲得從吸附的單分子膜上聚合並且形成高規則度的高分子膜。

Electrochemical Scanning Tunneling Microscopy (EC-STM) and Cyclic Voltammetry (CV) are utilized to study the adsorption behavior of 3,4-ethylenedioxythiophene (EDOT) from phosphate buffer solution onto Au(111) surface, as well as the electro-polymerization of the EDOT monolayer into poly-ethylenedioxythiophene (PEDOT). The results show that EDOT molecules can oxidative adsorption on gold surface, forming a monolayer with various ordered adlattices of (4×5), (3×2√13), (3×7) and (5×√3), as confirmed by the in-situ observation of STM. The oxidation adsorption is initiated at a potential of -0.25 V (vs Pt reference electrode) and the adsorption monolayer desorbs at a more negative potential (-0.4V). When the adsorption is performed at a lower potential, the monolayer forms slowly and, therefore, a more ordered monolayer can be obtained. To perform the polymerization, a potential higher than 0.2 V should be applied. However, if the electrode is controlled at the constant potential, the EDOT monomers in the solution will take part in the reaction on the electrode, leading to a disordered PEDOT layer with multilayered structure. On the contrary, if a cyclic potential (-0.25 V – 0.25 V) is applied after formation of an ordered EDOT monolayer, the polymerization will perform mainly on the adsorbed molecules and an ordered PEDOT monolayer can be obtained.

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