隨著科技的蓬勃發展，人們發現地球正面臨著嚴重的環境破壞以及資源耗竭的危機，使得聯合國在2015年通過巴黎協定以確定永續環境的目標，因此如何以永續環境的方式收集電能成為各國正視的問題。在研究中，我們由二維材料氧化石墨烯製作出層狀奈米通道薄膜，利用凡德瓦力使通道空間控制於約 0.8 nm並堆疊約12000層，並利用通道於氯化鉀電解液下重疊電雙層的特性，使薄膜具有離子選擇性，再結合溫度或離子熱電效應與鹽度梯度的作用而產生電流。當溫度或濃度梯度增大時，最大功率密度增加，測得的最大功率密度為1.57 W/m2，而離子選擇性和能量轉換效率隨著濃度梯度降低而增加，獲得最佳能量轉換效率為46.5%。由於奈米通道中的熱電效應與鹽度梯度具有協同作用，當通道具有跨模溫度差時，施加負溫度梯度產生的最大功率密度效果會比施加正溫度梯度佳，其測得的最大功率密度為不施加任何溫度時的1.6倍。若在模擬海水與淡水之濃度的電解液中施加溫度並改變其pH值的情況下，表面電荷密度隨著pH值增加而提升，於pH10時測得最大功率密度為0.85 W/m2。本研究目標為更了解薄膜的特性，如溫度與表面電荷的效應、鹽度梯度發電受溫度之響應等，以準確使用並開發出穩定的薄膜裝置，讓廢熱運用在海水與淡水間，製造出對環境友善的再生能源。

The collection of electrical energy in a sustainable manner has become a matter of paramount importance for worldwide due to energy crisis facing our planet. In this study, we fabricated a layered nano-channel membrane using graphene-oxide two-dimensional material. By employing van der Waals forces, we controlled the channel spacing to approximately 0.8 nm and stacked approximately 12,000 layers. Leveraging the overlapping electric double layer characteristics of the channel in a potassium chloride electrolyte, the membrane exhibited ion selectivity. This, combined with the effects of temperature or ion thermoelectric phenomena and salinity gradient, resulted in the generation of electric current. As the temperature or concentration gradient increased, the maximum power density also increased. The measured maximum power density was 1.57 W/m2. Moreover, ion selectivity and energy conversion efficiency increased as the concentration gradient decreased, with the optimal energy conversion efficiency reaching 46.5%. The synergistic effects of thermoelectric phenomena and salinity gradient in the nano-channel were observed, whereby applying a negative temperature gradient across the channel yielded a maximum power density effect greater than that of applying a positive temperature gradient. The measured maximum power density in the former case was 1.6 times higher than that without any temperature gradient. When simulating the electrolyte with varying pH values in the concentration of simulated seawater and freshwater, the surface charge density increased with the rise in pH. At pH 10, the measured maximum power density was 0.85 W/m2. Overall, this study provides a deeper understanding of the characteristics of the membrane, such as the effects of temperature and surface charge, as well as the response of salinity gradient power generation to temperature. This knowledge is enable us to utilize and develop stable membrane devices, thereby harnessing waste heat between seawater and freshwater to produce environmentally friendly renewable energy.

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