關於有機硫醇分子在自組裝分子膜(Self-assembled monolayer)領域的研究備受關注，近年來更是專注於雜環硫醇分子的應用，而其作為電鍍銅時的有機添加劑也同樣備受重視。吡啶(Pyridine)官能基的有機硫化物被廣泛研究，目前研究表明吡啶硫醇分子可應用於促進細胞色素C的電子轉移、沉澱廢水中的重金屬、溶解金屬金以及抑制銅溶解，然而它們在界面電化學的吸附狀態及型式尚未被充分探討。本研究第一部分透過循環伏安法(CV)以及掃描式穿隧電子顯微鏡(STM)，探討了2-巰基吡啶2-MPY (2-Mercaptopyridine)、2-巰基吡啶-3-羧酸2-MPYA (2-Mercaptopyridine-3-carboxylic acid)分子在金(111)電極上的吸附行為，並將結果與MMI (2-Mercapto-1-methylimidazole)、4-MPY (4-Mercaptopyridine)做比較，接著透過改變電位控制、pH值、陰離子、製備溶液的影響觀察分子在金(111)表面上的變化。結果闡明2-MPY/H2O、2-MPY/EtOH分子在pH1 硫酸、pH3 硫酸鉀、0.1 M 過氯酸中在正電位0.3 V至0.9 V之間皆可觀察到穩定的分子結構，證明結構具有相當好的穩定度，並不會受到溶劑的影響。透過高解析的STM影像圖分析2-MPY/H2O、2-MPY/EtOH、MPYA分子吸附方式。觀察到分子吸附期間並未觀察到典型硫醇分子所形成的S-Au-S結構，以及其所造成的缺陷，分子皆以S、N直接吸附於金 (111)表面上，而這樣的結果與本研究所選用的分子結構和金表面形成的鍵結有關。MPYA分子在pH1 硫酸中在正電位0.3 V至0.9 V之間皆可觀察到穩定的分子結構，證明結構亦具有相當好的穩定度。透過高解析的STM影像圖分析2-MPY/H2O、MPYA分子吸附方式一致，分子皆以S、N直接吸附於金 (111)表面上，但其中MPYA具有羧酸基(COOH)，其形成的氫鍵會使結構更穩定。本研究的第二部分則揭示了2-MPY、2-MPYA分子作為電鍍銅的添加劑的效果。兩結構差異在於是否具有羧酸基(COOH)，實驗證實2-MPY有顯著的抑制效果，而2-MPYA則有良好的加速效果(加速約3-4倍)。結果證實，本實驗對於2-MPY、2-MPYA的研究，有助於了解吡啶硫醇分子自組裝過程中的吸附機制，並在電鍍銅上有不錯的貢獻，希望未來可以有更多的應用。

Research on organic thiol molecules in the field of self-assembled monolayers (SAMs) has attracted significant attention, particularly the recent focus on heterocyclic thiol derivatives. These compounds have also garnered interest as organic additives in copper electroplating processes. Pyridine-functionalized organosulfur compounds have been extensively studied, and current findings indicate that pyridine-thiol molecules can promote electron transfer in cytochrome C, precipitate heavy metals from wastewater, dissolve gold, and inhibit copper dissolution. However, their adsorption states and configurations at electrochemical interfaces remain insufficiently understood.In the first part of this study, the adsorption behavior of 2-mercaptopyridine (2-MPY) and 2-mercaptopyridine-3-carboxylic acid (2-MPYA) on Au(111) electrodes was investigated using cyclic voltammetry (CV) and scanning tunneling microscopy (STM). Their behavior was compared to that of 2-mercapto-1-methylimidazole (MMI) and 4-mercaptopyridine (4-MPY). The effects of applied potential, pH, anions, and solvent environment on molecular arrangement were also examined.The results revealed that 2-MPY in both water and ethanol forms stable monolayers in pH 1 H₂SO₄, pH 3 K₂SO₄, and 0.1 M HClO₄ across a potential range of +0.3 V to +0.9 V, demonstrating excellent stability regardless of solvent. High-resolution STM images showed no typical S–Au–S thiolate structures or associated defects; instead, the molecules were found to adsorb directly via S and N atoms on the Au(111) surface—an outcome attributed to the specific molecular structures and binding modes involved.Similarly, MPYA formed stable structures in pH 1 H₂SO₄ within the same potential range, also confirmed through STM imaging to adsorb via S and N atoms. The presence of a carboxylic acid group (-COOH) in MPYA likely contributes to additional hydrogen bonding, further stabilizing the SAM structure.The second part of this study evaluated the performance of 2-MPY and 2-MPYA as additives in copper electroplating. The key structural difference lies in the presence of the –COOH group. Experimental data revealed that 2-MPY exhibited a strong suppressing effect, whereas 2-MPYA significantly accelerated the plating process by approximately 3–4 times.In conclusion, this study provides insights into the adsorption mechanisms of pyridine-thiol SAMs on gold surfaces and demonstrates their potential application as functional additives in copper electroplating, offering promising directions for future development.

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