麻省理工學(xué)院研究者稱通過更新燃料電池的內(nèi)部材料,可將便攜式消費電子產(chǎn)品所用燃料電池的功率輸出提高50%。
化學(xué)工程Bayer(乙酰水楊酸的乙酰衍生物)教授兼MIT研發(fā)小組帶頭人Paula Hammond在本周三發(fā)表的一份聲明中表示:“我們的目標是用這類成本有效、調(diào)節(jié)方便、性能更佳的材料取代傳統(tǒng)燃料電池的薄膜。”
MIT研究小組主要關(guān)注直接甲醇燃料電池(DMFC),這類燃料電池采用甲醇作為燃料,而不必要將乙醇(酒精)提純成氫來作為燃料。
目前DMFC的使用范圍尚受到一定限制。因甲醇能滲透兩電極間用作電解交換的Nafion膜,滲透至燃料電池的中心,從而導(dǎo)致燃料的浪費。
據(jù)研究人員稱,通過采用層-層組裝技術(shù),MIT研究人員發(fā)明了一種可取代Nafion的材料。并且可以調(diào)節(jié)薄膜的結(jié)構(gòu)(每次幾納米)。新型薄膜抗甲醇滲透能力提高了兩個等級,但是質(zhì)子傳導(dǎo)率比Nafion要好。
研究人員在Nafion質(zhì)子交換膜上包了一層新型薄膜并將其用于一塊DMFC,結(jié)果發(fā)現(xiàn)燃料電池的功率輸出上升了50%。
該研究小組稱其現(xiàn)在正著手研究這種新型質(zhì)子薄膜是否能夠取代Nafion膜。出于這種考慮,他們已經(jīng)單獨生產(chǎn)這種薄膜,這種薄膜在材質(zhì)上更像是保鮮膜。
作為MIT能源研究的一部分,該小組亦已開始研究這種材料在光電方面的用途。
DuPont-MIT聯(lián)盟曾對MIT的燃料電池研究提供資金支持,但目前這項研究由國家科學(xué)基金提供支持。
翻頁查看英文原文:
MIT team claims new fuel cell material
MIT researchers said they have improved the power output of one type of fuel cell by more than 50 percent. Their goal: portable electronics.
"Our goal is to replace traditional fuel-cell membranes with these cost-effective, highly tunable and better-performing materials," Paula Hammond, Bayer Professor of chemical engineering and leader of the research team, said in a statement released Thursday (May 15).
Hammond's team focused on direct-methanol fuel cells (DMFCs), in which the methanol is used as the fuel, eliminating the need to distill alcohol to hydrogen as a fuel.
Current DMFCs have limitations. Nafion, the material currently used for the electrolyte sandwiched between the electrodes, is permeable to methanol, allowing seepage across the center of the fuel cell, thereby wasting fuel.
The MIT researchers created an alternative to Nafion using a layer-by-layer assembly technique. They were able to tune the structure of their film a few nanometers at a time. The resulting thin film is two orders of magnitude less permeable to methanol, but compares favorably to Nafion in proton conductivity, according to the researchers.
The researchers coated a Nafion membrane with the new film and incorporated it into a DMFC. The result was an increase in power output of more than 50 percent.
The team said it is now exploring whether the new film could be used to replace Nafion. To that end, they have been generating thin films that stand alone, with a consistency much like plastic wrap.
The team has also begun exploring the new material's use in photovoltaics as part of the MIT Energy Initiative.
The fuel cell research was supported by the DuPont-MIT Alliance. It is currently supported by the National Science Foundation.
