Ionic liquids (ILs) have shown to be promising additives to the catalyst layer to enhance oxygen reduction reaction in polymer electrolyte fuel cells. However, fundamental understanding of their role in complex catalyst layers in practically relevant membrane electrode assembly environment is needed for rational design of highly durable and active platinum-based catalysts. Here we explore three imidazolium-derived ionic liquids, selected for their high proton conductivity and oxygen solubility, and incorporate them into high surface area carbon black support. Further, we establish a correlation between the physical properties and electrochemical performance of the ionic liquid-modified catalysts by providing direct evidence of ionic liquids role in altering hydrophilic/hydrophobic interactions within the catalyst layer interface. The resulting catalyst with optimized interface design achieved a high mass activity of 347 A g⁻¹_Pt at 0.9 V under H₂/O₂, power density of 0.909 W cm⁻² under H₂/air and 1.5 bar, and had only 0.11 V potential decrease at 0.8 A cm⁻² after 30 k accelerated stress test cycles. This performance stems from substantial enhancement in Pt utilization, which is buried inside the mesopores and is now accessible due to ILs addition.

离子液体（IL）已被证明是有前途的催化剂层添加剂，可增强聚合物电解质燃料电池中的氧还原反应。然而，为了合理设计高度耐用和活性的铂基催化剂，需要对它们在实际相关的膜电极组件环境中的复杂催化剂层中的作用有基本的了解。在这里，我们探索了三种咪唑衍生的离子液体，因其高质子传导性和氧溶解度而被选择，并将它们合并到高表面积炭黑载体中。此外，我们通过提供离子液体在改变催化剂层界面内的亲水/疏水相互作用中的作用的直接证据，建立了离子液体改性催化剂的物理性质和电化学性能之间的相关性。具有优化界面设计的所得催化剂在H ₂ /O ₂下在0.9V下实现了347 A g ^-1 _Pt的高质量活性，在H ₂ /空气和1.5巴下功率密度为0.909 W cm ^-2 ，并且具有仅0.11 30 k 加速应力测试循环后，V 电位下降至 0.8 A cm ^-2 。这种性能源于铂利用率的显着提高，铂埋在中孔内，现在由于添加了离子液体而可以使用。