1D Package‐Integrated Platinum Catalyst with Robust Interactions for Enhanced Cathodic Oxygen Reduction

Abstract Durable electrocatalysts and optimal ionomer distribution in cathode catalyst layer (CCL) are crucial for the efficiency and lifetime of proton exchange membrane fuel cells (PEMFCs), especially at high currents. This work presents a 1D package‐integrated platinum (Pt) catalyst designed to optimize mass exchange and boost cathodic oxygen reduction reaction (ORR). The package‐integrated Pt catalyst not only enhances the active site utilization, activity, and stability of Pt alloys but also optimizes the ionomer coverage and oxygen transport within the CCL. It shows superior performance with a mass activity of 1.33 A mg Pt −1 and only a 12 mV decay in half‐wave potential after 30 000 cycles. Additionally, it delivers impressive catalytic performance (320 mA cm −2 at 0.8 V), mass transport polarization (0.632 V at 2000 mA cm −2 ), and low oxygen transport resistance (0.03 s cm −1 ) in hydrogen‐air fuel cells. This package‐integrated catalyst with robust anti‐ionomer interference and impressive transport capability is of great significance for designing efficient and long‐lasting PEMFC cathodes.