Krause Kevin, Garcia Marine, Michau Dominique, Clisson Gérald, Billinghurst Brant, Battaglia Jean-Luc, Chevalier Stéphane
Arts et Métiers Institut de Technologie, CNRS, Université de Bordeaux, Bordeaux INP, Institut de mécanique et d'ingénierie (I2M), 33405 Talence, France.
Université de Bordeaux, CNRS, Bordeaux INP, Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), F-33600 Pessac, France.
Lab Chip. 2023 Sep 13;23(18):4002-4009. doi: 10.1039/d3lc00380a.
Polymer electrolyte membrane (PEM) electrolyzers are renewable energy storage systems that produce high purity hydrogen fuel from electrochemical water splitting. The PEM in particular is a key component that acts as a solid electrolyte between electrodes and separates the reactants, but despite these benefits, its internal ion transport mechanisms are not fully understood. Here, the first microfluidic PEM electrolyzer that is semi-transparent in the infrared (IR) spectrum is developed as a platform for characterizing the PEM hydration during operation. The electrochemical performance of the chip is compared to its PEM hydration, which is measured synchrotron Fourier-transform infrared (FTIR) spectroscopy. The PEM water content is directly probed in the operating electrolyzer by measuring the transmitted light intensity at wavelengths around 10 μm. By supplying the electrolyzer with reactant starving flow rates, mass transport driven cell failure is provoked, which coincides with membrane dehydration. Furthermore, higher operating temperatures are observed to improve the stability in membrane hydration through increasing the membrane water uptake. The methods presented here prove the viability of IR techniques for characterizing membrane hydration, and future extension towards imaging and thermography would enable further quantitative studies of internal membrane transport behaviors.
聚合物电解质膜（PEM）电解槽是一种可再生能源存储系统，可通过电化学水分解产生高纯度氢气燃料。特别是PEM，它是一种关键组件，在电极之间充当固体电解质并分离反应物，但尽管有这些优点，其内部离子传输机制尚未完全了解。在此，开发了第一种在红外（IR）光谱中半透明的微流控PEM电解槽，作为表征运行期间PEM水化的平台。将芯片的电化学性能与其PEM水化进行比较，PEM水化通过同步加速器傅里叶变换红外（FTIR）光谱测量。通过测量10μm左右波长处的透射光强度，在运行的电解槽中直接探测PEM的含水量。通过向电解槽供应反应物饥饿流速，引发传质驱动的电池故障，这与膜脱水同时发生。此外，观察到较高的运行温度通过增加膜的吸水量来提高膜水化的稳定性。这里介绍的方法证明了红外技术用于表征膜水化的可行性，并且未来向成像和热成像的扩展将能够对内部膜传输行为进行进一步的定量研究。
