Quaternized aryl ether-free polyaromatics for alkaline membrane fuel cells: synthesis, properties, and performance - a topical review

Quaternized aryl ether-free polyaromatics are an important family of polymer electrolytes for alkaline membrane fuel cells (AMFCs) due to their outstanding alkaline stability. In this review, state-of-the-art quaternized aryl ether-free polyaromatics are discussed with respect to their synthesis and preparation. The mechanical and electrochemical properties and alkaline stability of the polyaromatics that impact AMFC performance and durability are discussed in comparison with aryl ether-containing polyaromatic and polyolefinic electrolytes. Their performance in membrane electrode assemblies (MEAs) is discussed with emphasis on the area specific resistance and phenyl group adsorption on hydrogen oxidation catalysts. The AMFC performance of MEAs employing state-of-the-art aryl ether-free polyaromatics is compared with those employing polyolefins and aryl ether-containing polyaromatics. Finally, the limitations and outlook of quaternized aryl ether-free polyaromatics are briefly summarized.