Enhancing Water Management with Three-Dimensionally Micropatterned Anion Exchange Membranes for Alkaline Fuel Cells

Alkaline exchange membrane fuel cells (AEMFCs) offer a promising solution for clean hydrogen utilization. However, effective water management remains a challenge due to the concurrent generation and consumption of water at the electrodes, which impacts the efficiency of AEMFCs at high current densities. Here, we report the fabrication of alkaline fuel cells with improved water management by employing a three-dimensionally patterned alkaline exchange membrane (AEM) at the interface with the cathode catalyst layer. This micropatterned AEM, made by soft lithography, enables a power density of 628 mW cm–2 at a current density of 1100 mA cm–2, representing an approximately 50% performance improvement over identical AEMFCs made from conventional two-dimensional AEMs. The patterned AEM also improves platinum utilization due to the increased catalyst-membrane contact area and tailored catalyst layer thickness.