本研究利用表面增顯紅外線光譜儀(SEIRAS)結合循環伏安儀(CV)，以即時測定的方式記錄在過氯酸水溶液中，硫醇及胺基分子於多晶金表面上的吸附行為，同時探討不同頭基及尾基對分子吸附特性的差異。在SEIRAS光譜上的分析，主要是利用分子碳鏈上亞甲基(-CH2-)於波數2800 ~ 3000 cm-1振動帶範圍內的訊號強度來判定吸附量的多寡以及分子的吸附位向。實驗結果顯示，金電極表面在施加偏正電位時(-0.1 V vs. Pt)比在開路電位狀態下(OCP：-0.6 V vs. Pt)能具有較高的硫醇分子吸附量，而胺基分子的吸附量則無顯著的差異，但在OCP狀態下比在正電位時更容易有存在於溶液中的質子化胺基分子接近電極周圍，排開較多的表面水分子而影響波數3400 ~ 3600 cm-1範圍的訊號強度。
依據SEIRAS的表面選擇規則，在金屬/溶液的界面中，偶極矩的變化必須垂直於表面，才具備SEIRAS放大訊號的功效，在此即當吸附的分子碳鏈越靠近於表面時，亞甲基振動帶出現的特徵峰強度越強，反之當碳鏈越遠離時則強度越弱。因此由實驗結果可知，當分子之尾端為硫醇官能基時，因硫醇與金表面具有較強之吸引力，分子會以近乎平躺之位向於表面;當尾端為較疏水性的甲基時，分子在表面呈現傾斜;而當尾端為具親水性的羥基時，分子則在表面有接近直立的吸附位向。

A surface-enhanced infrared spectroscopy (SEIRAS) combined with cyclic voltammetry (CV) was utilized to study the adsorption behaviors of thiol and amine molecules on the surface of polycrystalline gold in an aqueous solution of perchloric acid (HClO4) and the differences in molecular adsorption caused by different head and terminal groups. It is mainly analyzed by the signal intensity of the methylene group (-CH2-) on the molecular carbon chain in the vibration band of the wave number range of 2800 ~ 3000 cm-1 to determine the amount of adsorption and the adsorption orientation of the molecule.
The experimental results show that the gold electrode surface have a higher molecular adsorption amount of thiol when the positive potential is applied (-0.1 V vs. Pt) than the open circuit potential (OCP: -0.6 V vs. Pt), but for amine is no significant difference. However, the protonated amine molecules present in the solution are easier to near the electrode at OCP state than at positive potential, so more surface water molecules are repelled to affect the signal strength in the wave number range of 3400 ~ 3600 cm-1.
According to the surface selection rule of SEIRAS, in the metal/solution interface, the dipole moment must be perpendicular to the surface to have the effect of amplification signal, where the carbon chain of molecule adsorbed is closer to the surface, the characteristic peak (C-H) intensity is stronger, but is weaker when the carbon chain is farther away. Therefore, it can be seen from the experimental results that when the terminal group is thiol making the molecule lie on the surface, is hydrophobic methyl group making the molecule tilt on the surface and is hydrophilic hydroxyl group making the molecule stand on the surface.

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