Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
J Am Chem Soc. 2010 Mar 17;132(10):3400-4. doi: 10.1021/ja908638d.
Fuel cells are energy conversion devices that show great potential in numerous applications ranging from automobiles to portable electronics. However, further development of fuel cell components is necessary for them to become commercially viable. One component critical to their performance is the polymer electrolyte membrane, which is an ion conductive medium separating the two electrodes. While proton conducting membranes are well established (e.g., Nafion), hydroxide conducting membranes (alkaline anion exchange membranes, AAEMs) have been relatively unexplored by comparison. Operating under alkaline conditions offers significant efficiency benefits, especially for the oxygen reduction reaction; therefore, effective AAEMs could significantly advance fuel cell technologies. Here we demonstrate the use of ring-opening metathesis polymerization to generate new cross-linked membrane materials exhibiting high hydroxide ion conductivity and good mechanical properties. Cross-linking allows for increased ion incorporation, which, in turn supports high conductivities. This facile synthetic approach enables the preparation of cross-linked materials with the potential to meet the demands of hydrogen-powered fuel cells as well as direct methanol fuel cells.
燃料电池是一种能量转换设备，在从汽车到便携式电子产品等众多应用中具有巨大的潜力。然而，为了使燃料电池组件具有商业可行性，还需要进一步开发。对其性能至关重要的一个组件是聚合物电解质膜，它是分隔两个电极的离子传导介质。虽然质子传导膜已经得到很好的研究（例如，Nafion），但与质子传导膜相比，氢氧根传导膜（碱性阴离子交换膜，AAEM）的研究相对较少。在碱性条件下运行具有显著的效率优势，特别是对于氧还原反应；因此，有效的 AAEM 可以显著推进燃料电池技术。在这里，我们展示了使用开环复分解聚合来生成具有高氢氧根离子电导率和良好机械性能的新型交联膜材料。交联允许增加离子的掺入，从而支持高电导率。这种简便的合成方法能够制备交联材料，有可能满足氢燃料电池和直接甲醇燃料电池的需求。
