Progress in High-Performance Anion Exchange Membranes Based on the Design of Stable Cations for Alkaline Fuel Cells

Solid alkaline fuel cells with anion exchange membranes (AEMs) have drawn wide attention and have become an important focus in the field of renewable energy cells in recent years due to their high electrode activity, potential application of non-precious metal catalysts, and relatively low requirements for fuel purity. AEM is the central component in solid alkaline fuel cells, and plays the role of conducting ions, blocking fuel crossover and providing catalyst support in fuel cells. Its performance directly affects the efficiency and service life of fuel cells. With some exceptions, the majority of AEMs have relatively low hydroxide conductivity and poor durability, which cannot meet the requirements of practical applications. The past decade has witnessed great progress in AEM designs and stability. Various kinds of AEMs with different cationic structures have been designed, and their properties and application in fuel cells are investigated. This review provides a comparative investigation and summary of highlights from the design of cationic structures for AEMs, including cyclic and spirocyclic quaternary ammonium cations, modified quaternary phosphonium, modified imidazoles, guanidinium, and metal cations. The authors' perspective on the remaining challenges and directions of AEMs research for future development are also discussed.

Automated summary

Solid alkaline fuel cells with anion exchange membranes (AEMs) have been a focus in renewable energy cells due to their high electrode activity, potential for non-precious metal catalysts, and lower fuel purity requirements. The past decade has seen significant progress in AEM designs, with various cationic structures being explored, though challenges remain in improving hydroxide conductivity and durability. Future research directions include addressing these challenges.