In the production of catalyst‐coated membranes (CCMs) for proton‐exchange membrane fuel cells and electrolyzers, the ink formulation and its processing are key factors in determining the resulting catalyst layer. Catalyst inks often contain a multicomponent solvent mixture. Selective drying, which can occur with solvent mixtures, changes the composition in the solidifying film and thus influences the microstructure of the layer that forms. The selectivity depends on the material‐specific thermodynamics of the solvents and the process‐related drying parameters. Different 1‐propanol/water mixtures serve as the state of the art material system considered and commonly used for CCM inks. Typical solvent mixtures can be dried selectively or non‐selectively, depending on the initial ink composition and humidity of the drying air. In mixtures that contain more 1‐propanol than the azeotropic or arheotropic composition, the 1‐propanol content accumulates in the remaining liquid; if there is less, it decreases. Increasing the preloading of the drying air with water leads to a relative water enrichment and shifts the tipping point to higher initial alcohol fractions. This behavior can be transferred to the real CCM production.

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关于燃料电池和电解槽 CCM 油墨的干燥现象：1-丙醇/水混合物蒸发的选择性

在质子交换膜燃料电池和电解槽的催化剂涂层膜（CCM）的生产中，油墨配方及其加工是决定最终催化剂层的关键因素。催化剂油墨通常含有多组分溶剂混合物。溶剂混合物中可能发生的选择性干燥会改变固化膜的成分，从而影响所形成层的微观结构。选择性取决于溶剂的材料特定热力学和与工艺相关的干燥参数。不同的 1-丙醇/水混合物作为 CCM 油墨考虑和常用的最先进材料系统。典型的溶剂混合物可以选择性地或非选择性地干燥，具体取决于初始油墨成分和干燥空气的湿度。在含有比共沸或均流组合物更多 1-丙醇的混合物中，1-丙醇含量在剩余液体中累积；如果少了，就会减少。增加干燥空气的水预载量会导致水相对富集，并将临界点转移到更高的初始酒精分数。这种行为可以转移到真正的CCM生产中。