近年來能源短缺的問題一直不斷的衍生出來，許多學者積極尋找可替代的能源，鹽分梯度能源是一種乾淨無汙染的可持續性再生能源，它存在淡水與海水的交界處，利用濃度的不同可將吉布斯自由能轉換成電能，是一種新穎的能量轉換裝置，目前鹽類梯度能源研究的方式以壓力延緩逆滲透與可逆電透析兩種為主。
本研究利用可逆電透析的原理來進行發電，並採用市面上可購得的奈米膜（原先用於生醫方面的薄膜）取代原先的離子交換膜，因為奈米維度下，電雙層重疊效應會更加明顯，可比原先的離子交換膜有更好的功率及轉換效率，而此研究我們選擇了Polycarbonate 以及 Aluminum Oxides membrane 分別為陽離子選擇性及陰離子選擇性的薄膜,在KCl，NaCl，LiCl 三種電解液不同濃度下（0.1mM|1mM , 3mM , 10mM , 30mM , 100mM）進行研究,分別探討了擴散電壓，擴散電流，電流－電壓曲線，輸出功率，離子遷移數，轉換效率，最後是功率密度，從我們的研究裡可看的出來兩種膜的性質差異大，所對應的結果也不大相同，以Polycarbonate membrane 來說，其最大輸出功率可達3.47nW，而Aluminum Oxides membrane最大輸出功率則是346nW，這個結果已可供給一些微小生醫設備運作,且在未來具有潛力成為新一代的能源裝置。

Recently, the energy crisis has been arisen in the world. Many researchers are looking for alternative energy. The salinity gradient power is developed that completely renewable and sustainable in recent decades. The salinity power or the energy represented by the salinity concentration gradient between fresh water and seawater could become the next generation energy. The novel energy conversion device can convert Gibbs free energy into electricity. There are two technologies of converting energy: one is pressure retarded osmosis (PRO) and another is reverse electrodialysis (RED).
In this research, we use the principle of reverse electrodialysis for generating electricity, and replace the ion exchange membrane with nanopore membrane. Because in nanopore membrane the overlapped electric double layers become more obvious, therefore, the efficiency of power generation and energy conversion will be higher than ion exchange membrane. We choose the polycarbonate membrane as cation selectivity and aluminum oxides membrane as anion selectivity that can be demonstrated for energy conversion. Diffusion potential, diffusion current, I-V curve characteristics, power generation ,transference number ,energy conversion efficiency and power density were discussed in three different electrolyte( KCl, NaCl, LiCl ) and compared with different concentration gradient (0.1mM | 1mM, 3mM, 10mM, 30mM, 100mM).
The properties between the polycarbonate membrane and aluminum oxides membrane are very different. Thus, the maximum output power generation produced by polycarbonate membrane can obtain 3.47 nW, and aluminum oxide membrane can obtain 346 nW. This results can provide some biomedical microdevices to operate and can become the next generation of energy device.

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