ODNP of Fuel Cell Membranes

聚电解质膜燃料电池可以在较低的温度下运行，适合在消费电子产品和车辆中使用。以氢和氧为燃料的燃料电池会产生水，这会严重影响将阳极与阴极分开并对阳离子具有渗透性的膜的功能。为了设计高效的燃料电池，必须非常详细地了解不同水合水平下的膜功能。但是，水和离子在燃料电池膜中的传输是非均相的，并由膜的形态决定，膜的形态随其水化状态而变化。像扩散和松弛的拉普拉斯核磁共振以及Overhauser动态核极化(ODNP)等磁共振方法具有独特的能力，可以解开复杂的运输机制的异质性，并将它们分配到膜内不同的形态位置。这个项目在膜功能的研究中结合了两种磁共振方法，以解决关于膜水运输的相互矛盾的观点，并借助磁共振工具箱。一种新的用于膜功能的操纵性研究的装置将阐明和指定依赖于水分的膜结构和水分传输。

Polyelectrolyte membrane fuel cells can be operated at low temperature suitable for their use in consumer electronics and vehicles. Fueled by hydrogen and oxygen fuel cells produce water, which critically affects the function of the membrane that separates the anode from the cathode and is permeable to cations. To design efficient fuel cells, the membrane function must be understood in great detail for different hydration levels. But the water and ion transport though the fuel cell membrane is heterogeneous and determined by the membrane morphology, which changes with its hydration state. Magnetic resonance methods like Laplace NMR of diffusion and relaxation as well as Overhauser Dynamic Nuclear Polarization (ODNP) are unique in their capabilities of unraveling the complex heterogeneity of transport regimes and assigning them to the different morphological sites inside the membrane. This project combines both magnetic resonance methods in a study of membrane function to resolve conflicting views on membrane water transport with the help of a magnetic resonance toolbox. A novel set-up for in operando investigations of membrane function will clarify and specify the moisture-dependent membrane structure and water transport.