ABSTRACT Anion exchange membranes (AEMs) based on 1,2,3-triazolium quaternized PPO (TriPPO) functionalised with Graphene Oxide (GO), Zeolitic Imidazolate Framework-8 (ZIF-8), and Zeolitic Imidazolate Framework-67 (ZIF-67) AEMs were studied using MD simulations to compare their hydroxide transport and their stability against hydroxide degradation. The addition of ZIF8 and ZIF67 to TriPPO at higher hydration levels improved hydroxide transport by 53.0 % and 71.4 %, respectively, while adding GO showed no improvement, dropping it by 2.16 %. The highest self-diffusion coefficient of hydroxide ions (D OH ) of 3.64×10 −8 m 2 /s was obtained by the TriPPO3ZIF67 composite membrane. The higher D OH in TriPPO3ZIF67 is due to the smaller number of clusters (1.09), the shorter distance between adjacent cationic groups (7.5), and the higher number of water molecules (14.04) surrounding the cationic group. The degradation of the cationic group was evaluated, and the results showed that the N1 position of all the side chains is susceptible to hydroxide ion degradation. When comparing the AEMs, which are less susceptible to degradation in an alkaline medium, TriPPO3ZIF67 showed better stability against hydroxide ion attack due to a smaller number of hydroxide ions (4.03) around the cationic group and more water surrounding the hydroxide ions (24.12).
Letsau et al. (Fri,) studied this question.