最近的研究進展顯示直接甲醇燃料電池(DMFC)很有潛能成為交通運輸、固定的電力供應、以及可攜式的電子產品的電力來源。但是，DMFC仍然有一些主要的問題需要克服，才能應用在所謂3C的產品。擬以自然的物理力量作為甲醇溶液進料及二氧化碳產物排出之推動力，而不需要在微燃料電池裡設計需要動力來源之主動式推動元件。本研究考慮的自然的物理力量包括表面張力、蒸發、凝結及熱壓作用。採用這些自然力，將使微燃料電池不再需要主動式的微幫浦及相關的閥門而可簡化微燃料電池設計，減少其體積至8 cm3以下，並提昇其產生能量的效能及可靠度。本人研究目的在於設計一裝置能以不需外加能源的被動方式將微型燃料電池中的副產物-水與溶於其中的甲醇燃料回收於一固定容器。
本設計利用氣體擴散控制的自我組裝單分子層在二氧化矽晶圓表面上形成一具親疏水梯度性質的表面，此特性之表面可對微液珠產生驅動力量。預收集的蒸氣在此表面上凝結成液珠後，經由表面產生的毛細壓差將此微液珠帶開，並由後端建構的毛細微流道將液體導流至一多孔性的液體集中區。另外，設計中的疏水性氣孔將使氣態的二氧化碳由此處排出。
本研究包括此晶片的設計，製程與測試。製程方面包含了微機電製程中的反應式離子電漿深蝕刻，體型、面型微加工，高分子厚膜光阻膜造，與表面化學處理。測試部份則包括親疏水梯度結果量測，氣孔排氣測試，單微液珠測試，與蒸氣測試。
測試結果可觀查出此設計的確可達到原本預想之目的，不需外加動力的將液珠帶至一集中區，並使不凝結的氣體由氣孔排出，從實驗中所觀察到的液體處理速度遠比所估計的原本電池中的需求來的更有效率。

Direct methanol fuel cells (DMFC) have increasingly shown prospects serving as power source for transportation use, stationary power supply and portable electronic devices with the technical advances in the past decade. This research proposes a novel device to deal with the waste generated in μDMFC without external power. It employs natural fluidic physical phenomena, such as condensation, surface tension gradient and capillary force to separate vapor from gas, as well as collect and remove liquid droplets naturally. This device is fabricated by surface treatment with wettability gradient combined with SU-8 channels and DRIE through holes on silicon substrate. Testing results demonstrated very effective vapor condensation and liquid droplet collection and removal process on this simple device.

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