3-D Interlocking interface of membrane/catalyst layer for high robustness of hydrocarbon-based polymer electrolyte membrane fuel cell

Abstract

In polymer membrane electrolyte fuel cell field, hydrocarbon membrane has not been successfully employed for practical membrane-electrode assembly in spite of its high cost effectiveness compared to per-fluorinated sulfonic acid (PFSA) membrane. It is mainly attributed to an interface delamination originating from a poor interfacial adhesion between hydrocarbon membrane and PFSA-based catalyst layer. Here, we present 3-D interlocking layer (3-D ILL) formed at the interface of hydrocarbon membrane and PFSA based catalyst layer as a novel academic strategy to tackle the interface issue. It is realized by forming micro-porous skin on the both side of hydrocarbon membrane, filling the pores with PFSA ionomer. The PFSA ion-omer layer, therefore, physically binds the hydrocarbon membrane and catalyst layer. Owing to a highly in-terlocked structural feature, the interfacial adhesion is dramatically enhanced by 37-fold with the introduc-tion of the 3-D ILL. As a result of humidity cycling, an accelerated interfacial durability test, the MEA with 3-D ILL exhibits 10 times higher durability than the MEA with flat interface, clearly demonstrating its efficacy in enhancing the interfacial durability of hydrocarbon membrane-based fuel cell.