為了進行超臨界狀態下金屬材料的電化學行為分析並獲取相關的電化學參數，除了建立一套適用於溫度374 °C以上與壓力22.1 MPa以上的模擬超臨界水循環系統外，穩定且耐用的參考電極是不可或缺的。本論文主要研究目的在於發展高溫專用的Ag/AgCl參考電極以及Zr/ZrO2所製成的參考電極，並將其應用於超臨界水環境中，進行304L不鏽鋼電化學腐蝕電位(ECP)之量測，觀察其ECP在純水中隨溫度變化之情形。
測試結果發現在常溫下，氧化鋯管所製作成的Ag/AgCl參考電極經過72小時靜置時間後與商用Ag/AgCl參考電極同在飽和KCl溶液中的電位值差異皆小於10 mV以內，證明此高溫專用的Ag/AgCl參考電極在常溫環境下是可正常操作。並將氧化鋯管所製作成的Ag/AgCl參考電極應用於高溫288 °C、高壓7.8 MPa和溶氧濃度300 ppb之模擬沸水式反應器水環境下，與過去研究所製作的熱縮套管Ag/AgCl參考電極數據來互相比較，發現在相同條件下不同參考電極所測得的ECP值相近，並且氧化鋯管所製作成的Ag/AgCl參考電極量測出的ECP值可在短時間內達到平衡。後續也進行25 MPa及不同溫度下的304L試片ECP量測，可以發現ECP值在溫度由200℃、250℃升至300℃時，上升並不明顯，但在350℃時就會明顯上升。最後將Ag/AgCl參考電極以及Zr/ZrO2參考電極置於模擬超臨界水環境進行測試，分別在385℃和400℃之溫度進行量測，和350℃所測得之ECP相比，可以發現溫度及水進入超臨界狀態時因其物理性質改變所造成之阻抗上升為兩個影響ECP量測之重要因素。未來將利用此兩種參考電極進行不同的試片以及不同水化學環境的腐蝕電位測試。

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