燃料电池(fuel cell)已经可供商业化许多年，但目前只能使用纯氢气──这对实验室等机构来说很容易采购取得，要大量生产就嫌太贵；就算是最佳的燃料电池设计，也因为掺入取自天然气(有丰富来源)中的氢气所产生的一氧化碳毒化问题，很快就失败退场。

现在，来自美国康乃尔大学(Cornell University)的研究团队相信，他们能利用纳米科技提供一个解决方案，让氢燃料电池的商业化变得可行。

研究人员是在对氢燃料电池可能引起的一氧化碳毒化问题进行分析之后，研发出上述的解决方案。燃料电池会电化分解(electrochemically decompose)氢燃料，透过将其与氧气结合来剥离其电子，然后形成水蒸气──这也是燃料电池唯一的排放物。

然而，传统质子交换膜(proton exchange membrane，PEM)燃料电池，不但需要昂贵的铂/钌合金(platinum/ruthenium-alloy)做为阳极催化剂，这种催化剂也会因为很少量一氧化碳而被毒化。

目前市面上虽然存在商用解决方案，可为取自天然气中的氢涤除一氧化碳，但却因此让该种氢气的成本升高到不经济的程度。为了解决这种问题，由康乃尔大学能源材料中心(Energy Materials Center)教授Hector Abruna所率领的研究团队，利用纳米科技制造了一种成本比铂/钌合金低廉的催化剂，而且能耐受取自天然气之氢气中的一氧化碳浓度。

这种新型催化剂是由氧化钛(titanium oxide)与涂布了铂纳米粒子薄膜的钨(tungsten)所组成，最高可耐受2%的一氧化碳──这是能毒化纯铂催化剂的一氧化碳浓度之两百倍。

目前的氢燃料电池使用铂/钌合金做为阳极催化剂，康乃尔大学的研究团队则是用新研发的纳米催化剂来取而代之，并可望让燃料电池的商业化更为可行

目前研究人员已经在实验室中验证了以上的概念，现正在利用该种新型催化剂制作完整的PEM燃料电池。据了解，其燃料电池原型的耐久性表现到目前为止都优于早期失败的传统燃料电池；研究团队现在将确认新架构能够把燃料电池寿命延长到多少程度。

点击进入参考原文：Fuel cell breakthrough aims at commercialization, by R. Colin Johnson

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Fuel cell breakthrough aims at commercialization

by R. Colin Johnson

Fuel cells have been ready for commercialization for years, albeit only for use with pure hydrogen—easy to purchase for the lab, but expensive to mass produce. Even the best fuel cell designs become poisoned by impurities in hydrogen derived from natural gas—the most abundant source—causing them to fail prematurely. Now Cornell University scientists working for the U.S. Department of Energy (DoE) believe they have a cure using nanotechnology that could make hydrogen fuel cells commercially viable.

The scientists discovered the cure after analyzing the problem—carbon-monoxide poisoning. Fuel cells electrochemically decompose hydrogen fuel, stripping off its electrons by bonding it with oxygen to form water vapor—its only emission. However, the platinum/ruthenium-alloy catalyst used for the anode in traditional PEM (proton exchange membrane) fuel cells is not only expensive, but can be poisoned by exposure to even trace levels of carbon monoxide. Commercial methods exist for scrubbing carbon monoxide from the hydrogen produced from natural gas, but that inflates the cost of the hydrogen to uneconomical levels.

To solve the problem, a research team led by professor Hector Abruna of Cornell University's Energy Materials Center harnessed nanotechnology to fabricate a catalyst that is less expensive than platinum/ruthenium alloys and yet can tolerate levels of carbon monoxide found in hydrogen produced from natural gas.

The new catalyst is composed of titanium oxide and tungsten coated with a thin-film of platinum nanoparticles, resulting in a tolerance for as much as two-percent carbon monoxide—about 2,000 times more than the amount required to poison a pure platinum catalyst.

Now that the researchers have proven the concept in the lab, they are fabricating a complete PEM fuel cell using their new catalyst. So far the prototype fuel cells outlast traditional fuel-cells, which fail prematurely, and now the team wants to quantify for how long their new architecture will extend a fuel cell's life.

Other researchers contributing to the work included Cornell professor Francis DiSalvo, post doctoral researcher Deli Wang, research associate Hongsen Wang and doctoral candidates Chinmayee Subban and Eric Rus.