| 摘要: | 本研究案為整合研究提案 「燃料電池新材料開發及元件微成像研究」 之第一子計劃。整合研究提案內容包含(一) 新穎結構質子導體及電極材料於燃料電池之應用(中央大學 諸柏仁), (二) 多孔體系的核磁共振微成像(中山大學 丁尚武), (三)以及高性能甲醇燃料電池元件製作(第二年加入)。本子計劃目標在(1)開發新結構質子交換半透膜 (質子導體)及(2)高性能電化學活性觸媒二關鍵元件於氫氧燃料電池(PEMFC)或高溫型直接甲醇燃料電池(DMFC)。本研究第一部份衍生自過去開發PEM 材料相關經驗所啟發之關鍵學理問題，結合新近Nano-ionics 理論構建長程有序之軟物質探索其可能展現之優異的離子傳導特性，製備新穎奈米結構高分子半透膜材料使用於燃料電池。研究的手段乃經由瞭解PEM 材料奈米相分離空間型態及小分子（或離子）於奈米空間中之水合及遷移行為，探討奈米尺度下離子之傳輸偶合效應並從中增加對於PEM 材料微觀型態之理解。由上述研究結果我們將合成數種新型具規序性奈米結構之質子半透膜（或有機-無機混成）電解質，突破目前燃料電池質子傳導膜材料開發之瓶頸。本研究第二部份工作為研究在探討金屬氧化物奈米管結構及組成及觸媒附著(分散)與催化反應關聯性並獲致更優良材料。電極方面探討奈米氧化鈦管導電特性及其上所展現的催化活性及抗 CO 毒化性。由於新型奈米級自組裝構建之高分子半透膜為全新之材料設計觀念，且以金屬氧化物奈米管為燃料電池觸媒承載展現超高活性，將此首創之學理及發現推展至燃料電池領域，預期將有突破性之成果並超越國際之水準。 This proposal belongs to the fist sub-project of the joint proposal entitled Development of Novel Fuel Cell Materials and Micro-imaging Investigations of Devices: The joint project is composed of three part (1) Noval ionic conductor, and high electrochemical activity catalyst, (2) micro magnetic resonance imaging for porous systems, and (3) High activity direct methanol fuel cell devices (the group will be implemented the second year) Current proposal (the first subproject) is focused on the (1) development of novel proton conducting membrane and (2) continuing improvement of the high electrochemical active catalysts for fuel oxidation (methanol or H2) and for oxygen reduction used in hydrogen fuel cell (PEMFC) or high temperature type direct methanol fuel cell (DMFC) The first part of the work is based on our recent finding of an unusual ion conducting behavior between the organic and inorganic surfaces with activation energy lower than that in the polymer or in the solid surface. This finding is concurrent with the recently proposal Nano-ionic theory for solid ionics found for solid oxide materials with defects. Based upon the Nano-ionics theory, we have proposed that unique ion transport behavior may be envisaged when the nano-domains of the soft condensed materials are arranged in long range ordering. The nano-structured ion conducting materials is expected to deliver high proton conductivity under non-aqueous or low solvent conditions. The combination of characterization tools with theory is fundamental to fully illustrate the unique proton conduction behavior in the long range ordered nano-structured soft materials. Through the understanding, we hope to establish rules and directions for designing suitable materials with favorable ion conducting nano-structures. The second break-through is focused on the electrochemical catalytical activities of fuel cell catalysts. Currently, Pt based fuel cell catalysts suffered from low Pt utility, sensitive to CO poisoning, low electrochemical reaction rate (and thus low current out put). Out recent work shows when Pt catalyst is supported in metal oxide nano tube, the catalytically active nano particle (Pt for example) is highly dispersed on conducting porous metal oxide surface (also in the nano-meter dimension), which gives rise to higher reaction surface area fully accessible to the oxidants in the anode (including methanol, higher alcohol, oxalic acids, hydrogen) and the reluctant in the cathode (oxygen for example). In addition, the porous metal oxide plays to stabilize the nano particle, and changed the Pt (4f) density of state to release higher activity and also actively participate in removing the CO to prevent poisoning the Pt. Furthermore, the porous tube confined the oxidants and reactants for longer contact with the catalytical active nano particle to deliver more complete reaction, thus higher electricity output. Since the porous metal oxide is hydrophilic, it binds tightly with the binder to form the electrode and reduces the leaching of the catalysts. What metal oxide can deliver the best electronic conductivity and as the best support for Pt, and the details of the catalytical mechanisms rquires to be fully illustrated Since the self-assembly in the nano-scale for soft materials brings in new design concept for fuel cell membrane, and the use of metal oxide as Pt support is promising in revolutionalize current status of Fuel Cell catalyst development, it is fully expected that the content disclosed in the present proposal would results in technology break-through leads to new paradigm for fuel materials. 研究期間：9608 ~ 9707 |
