A Raman Spectroscopic Study of Radiation-Grafted Anion-Exchange Membranes Containing Different Anions

摘要

Anion exchange membranes (AEM) are being developed for use in a variety of electrochemical energy systems, such as alkaline membrane fuel cells, AEM-based electrolysers, reverse electrodialysis (RED), and redox flow batteries (RFB). The AEMs used will contain a variety of anions, depending on the application. For fuel cells and electrolysers (H_2 generating or CO_2 conversion), then alkaline anions such as OH~-, CO_3~(2-), and HCO_3~- are important. For RED cells and RFBs, non-alkali anions such as CI~-, HSO_4~-, and SO_4~(2-) are more relevant. If an AEM is synthesised using a methyl iodide reaction, then monitoring the ion-exchange of the resulting "as-synthesised" I~- forms to other forms, such as CI~-, is important as it is well known that it can be difficult to completely ion-exchange soft anions such as I~- out of AEMs (particularly those containing aromatic cationic groups).