Figure 8.

Surface modification of an anion exchange membrane (AEM) by infiltration and photo-cross-linking using 4,4-diazostilbene-2,2-disulfonic acid disodium salt (DAS). The azido group in DAS reacted to a nitrene group under UV irradiation which immobilized it on the membrane surface, thereby creating covalent cross-linking: The sulfonate group facilitated the water solubility and infiltration into the surface layer structure of the membrane, providing the negative charge groups and also improving the monovalent anion selectivity. Reproduced with permission from [57]. Copyrights 2018 American Institute of Chemical Engineers.