posted on 2024-01-04, 15:36authored byXiuqin Wang, Angela Mary Thomas, Rob G. H. Lammertink
The advancement of
anion exchange membranes (AEMs) with
superior
ionic conductivity has been greatly hindered due to the inherent “trade-off”
between membrane swelling and ionic conductivity. To resolve this
dilemma, macromolecular covalently cross-linked C-FPVBC-x AEMs were fabricated by combining partially functionalized ether-bond-free
polystyrene (FPVBC) with poly(arylene piperidinium). The results from
atomic force microscopy reveal that an increase in the ratio of FPVBC
promotes the fabrication of microphase separation morphology, resulting
in a high ionic conductivity of 40.15 mS cm–1 (30
°C) for the C-FPVBC-1.7 membrane. Molecular dynamics simulations
further examine the ionic conduction effect of cross-linked AEMs.
Besides, the unique cross-linking structure significantly improves
mechanical and alkaline stability. After treatment in 1 M KOH at 50
°C for 1200 h, the C-FPVBC-1.7 membrane shows only a 6.9% decrease
in conductivity. The C-FPVBC-1.7 AEM-based water electrolyzer achieves
a high current density of 890 mA cm–2 at 2.4 V (80
°C) and maintains good stability, enduring over 100 h at 100
mA cm–2 (50 °C). These results demonstrate
the significant potential of macromolecularly cross-linked AEMs for
practical applications in water electrolysis.