本研究運用化學還原法製備金奈米粒子/多壁奈米碳管複合材料修飾玻璃碳電極進行汞(Ⅱ)之循環伏安法分析，藉由調整汞(Ⅱ)溶液在不同pH條件及添加氯離子使汞(Ⅱ)主要物種分布改變下，瞭解修飾電極對汞(Ⅱ)主要物種改變之伏安法影響，最後瞭解修飾電極偵測水中不同濃度汞(Ⅱ)之還原電流值與濃度的相關性。由TEM、XRD、UV及EDS分析結果顯示利用化學還原法可有效製備金奈米粒子且與多壁奈米碳管複合狀況良好，而由電化學實驗可知修飾電極的反應面積皆大於玻璃碳電極，因此可得較大的偵測電流訊號值。當pH調整時，三種修飾電極皆會因汞(Ⅱ)主要物種分布改變而還原電位改變，但當氯離子添加時，僅10-GNP/MWCNTs修飾電極的偵測還原電位會偏移，最後修飾電極偵測不同濃度汞(Ⅱ)時，修飾電極的還原電流訊號值與汞(Ⅱ)濃度間(1 ppb ~ 10 ppb)的相關係數(R2)均有0.9以上是可信的線性關係，表示利用修飾電極伏安法分析汞(Ⅱ)是具有選擇性且可行的方法。;The objective of this work was to prepare gold nanoparticles (GNP)/ multi-walled carbon nanotubes (MWCNTs) composite to modified glassy carbon electrode (GCE), which was used to analyze Hg (Ⅱ) by cyclic voltammetry (CV). It was found that modification via GNP/MWCNTs composite increased the active area. In order to investigate the influences of speciation on the reduction peak currents, CV was conducted at different solution pH and with addition of NaCl. When the solution pH was adjusted, the shift of the reduction peak of Hg was measured by all three modified electrodes. When NaCl was added, only the GCE electrode modified by 10-GNP/MWCNTs measured the shift of the reduction peak of Hg. These indicated that the CV by GNP/MWCNTs modified GCE electrodes can monitored the changes in speciation. Linear response between the reduction peak current and Hg concentration ranged from 1 ppb to 10 ppb has been found in all three modified electrodes This suggested that using GNP/MWCNTs modified GCE electrodes to analyze Hg concentration via cyclic voltammetry may be feasible.