多數的固態熱電材料通常無法應用在低溫的廢熱回收，本研究以氧化石墨烯奈米通道薄膜結合電解液提供一低溫廢熱熱電轉換的可能性，並探討通道內溫度差驅動離子傳輸的各種效應，對於未來液態離子熱電材料的應用與材料的選擇提供一些基礎的資訊。本研究結合氧化石墨烯薄膜與電解溶液，透過氧化石墨烯奈米通道內之電雙層重疊建構出離子選擇性通道，在非均勻溫度場作用下，研究系統的熱電響應，即席貝克係數。本研究使用五種不同濃度的氯化鉀溶液進行氧化石墨烯奈米通道熱電響應的探討，結果顯示離子熱電響應隨著氯化鉀濃度降低而增大，當氯化鉀濃度為10-4 M時，可獲得最高的席貝克係數-0.69 mV/K。關於氧化石墨烯奈米通道內的離子熱電響應機制，本研究認為有三種溫度差驅動離子傳輸效應同時作用於其中，分別為「索爾特效應」、「熱滲透」及「溫度依賴性離子電遷移」，根據實驗與數值模擬分析，可發現傳統的「索爾特效應」及非滑移的「熱滲透」效應皆遠小於「溫度依賴性離子電遷移」效應，因此確定了奈米通道內的離子熱電響應主要是由「溫度依賴性離子電遷移」效應所主導，此效應隨著電解液濃度降低而顯著提升。此研究結果將有助於未來二維材料應用於低階熱能離子熱電轉換之發展。

In this study, a graphene oxide membrane is applied to the thermoelectric conversion of waste heat at a low temperature. A KCl solution is combined with the graphene oxide nanochannel membrane, and the best Seebeck coefficient of -0.69 mV/K is obtained at a solution concentration of 10-4 M KCl. The thermoelectric response of the graphene oxide nanochannels was studied at five different concentrations of KCl solution under a non-uniform temperature field. The results show that the ionic thermoelectric response increased with the decreases in the KCl concentration. Three ion thermoelectric mechanisms acting on the nanochannel were proposed: "the Soret effect," "thermo-osmosis," and "temperature-dependent ion electromigration." According to an analysis of the experimental results, it was found that temperature dependent ion electromigration was dominant in the nanochannel, and its effect was increased significantly with decreases in the KCl solution concentration.

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