Titanium-based porous transport layers (PTL) used in polymer electrolyte membrane (PEM) water electrolyzers suffer from surface passivation (titanium oxidation), which increases the interface resistance between the PTL and electrode. For long-term operation, PTLs are typically coated with considerable amounts of platinum or gold to ensure reasonable performance profiles over time. Moreover, it is well known that the oxide forms of platinum and gold are not stable under electrolysis conditions. In this study, an easy and scalable method is introduced to protect the titanium PTL from passivation by sputtering very thin layers of iridium onto commercially-available titanium PTLs. The iridium layer reduces the overall ohmic resistance of the PTL/catalyst layer interface and improves the cell's performance to that achieved with carbon-based PTLs. The coating process homogeneously deposited iridium throughout the inner structure of the PTL. The findings of this study may lead to the use of iridium as a protective layer for titanium PTLs, potentially enable operation at increased cell voltages and lead to increased electrolyzer durability.

用于聚合物电解质膜（PEM）电解槽的钛基多孔传输层（PTL）遭受表面钝化（钛氧化），这增加了PTL和电极之间的界面电阻。对于长期运行，PTL通常涂有大量的铂或金，以确保随时间推移提供合理的性能。此外，众所周知，铂和金的氧化物形式在电解条件下不稳定。在这项研究中，引入了一种简单且可扩展的方法，通过将非常薄的铱层溅射到市售的钛PTL上来保护钛PTL免受钝化。铱层降低了PTL /催化剂层界面的整体欧姆电阻，并将电池的性能提高到了碳基PTL所能达到的性能。涂覆工艺在整个PTL的内部结构中均匀沉积了铱。这项研究的发现可能会导致将铱用作钛PTL的保护层，从而有可能在增加的电池电压下工作并导致电解槽的耐用性增加。