本研究主要利用循環伏安法，以不同電極探討單純硫代硫酸根離子及不同濃度之硫代硫酸根離子添加於0.1wt%氯化鈉水溶液中之電化學性質。
由實驗結果顯示，於循環伏安法測試中，掃瞄速率（Scan rate）越快，所產生之遲滯環路（Hysteresis loop）越大，其電流值約與掃瞄速率的平方根成正比。
白金電極於不同濃度之硫代硫酸鈉溶液中，於0.1~0.8 VSCE電位範圍間，其電流主要的貢獻是來自於水的氧化與還原，換言之，硫代硫酸根離子在此電位範圍間不會有明顯之反應。在不同濃度之硫代硫酸鈉添加0.1wt% 氯化鈉後，並不會影響其原本未添加時所進行之反應。
鎳基690合金在添加不同濃度硫代硫酸根離子之0.1wt%氯化鈉溶液中，當添加硫代硫酸根濃度為0.001M時，硫代硫酸根的添加會促進孔蝕的生成，當添加硫代硫酸根濃度提高至0.01M時，此時之電流密度會小於在單純0.1wt%氯化鈉水溶液中之電流密度，且沒有孔蝕的生成。然而當添加的硫代硫酸根濃度至0.1M時，孔蝕仍不會發生。

Cyclic voltammetry was used to investigate the electrochemical behavior of different electrodes in plain thiosulfate and thiosulfate containing 0.1 wt% sodium chloride solutions. The results show that the faster the scan rate is set, the larger the hysteresis loop is obtained for all tested electrodes. Furthermore, the current densities are increased proportionally with square root of scan rate.
For platinum electrode in plain thiosulfate solution, the results show that the current density increases with concentration of thiosulfate ions especially of 0.1M. In the potential range of 0.1 to 0.8 V, the current is mainly contributed from the oxidation and reduction of water. In other words, the electrochemical reaction of thiosulfate ions does not take place in this region. Cyclic voltammetry of platinum in thiosulfate containing 0.1 wt% sodium chloride solution was also conducted. The presence of Cl- did not effect the electrochemical reaction as compared with that in plain thiosulfate solution.
For Alloy 690, no pit was be found in all concentration of plain thiosulfate solution tested. In 0.1 wt% of sodium chloride, the addition of 0.001 M thiosulfate solution, promoted pitting corrosion of 690 alloy. Nevertheless, a result of reducing current density was found in higher concentration of thiosulfate solution, such as 0.01 M and 0.1 M thiosulfate was add to 0.1 wt% NaCl solutions. No pit was observed in these solutions.

中文摘要I
英文摘要III
總目錄IV
表目錄VI
圖目錄VII
第一章 前言1
第二章 相關文獻及理論4
2-1 循環伏安法4
2-2 孔蝕機構6
2-2-1 孔蝕簡介6
2-2-2 鈍化現象的崩解7
第三章 實驗原理與實驗步驟9
3-1 材料9
3-2 試片前處理9
3-2-1 鎳基690合金電極10
3-2-2 白金電極10
3-3 測試溶液11
3-4 電化學測試11
3-4-1 循環極化曲線量測11
3-4-2 循環伏安法12
第四章 結果與討論14
4-1 硫代硫酸根離子濃度對鎳基690合金孔蝕性值之影響14
4-2 硫代硫酸根離子之電化學行為15
4-2-1 掃瞄速率的影響15
4-2-2 以白金為工作電極16
4-2-2-1 於單純氯化鈉水溶液環境16
4-2-2-2 於單純硫代硫酸鈉水溶液環境17
4-2-2-3 於含硫代硫酸鈉之氯化鈉水溶液環境18
4-2-3 以鎳基690為工作電極19
4-2-3-1 於氯化鈉水溶液環境19
4-2-3-2 於硫代硫酸鈉水溶液環境20
4-2-3-3 於含硫代硫酸鈉之氯化鈉水溶液環境21
第五章 結論26
第六章 參考文獻28

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