Achieving High Conductivity at Low Ion Exchange Capacity for Anion Exchange Membranes with Electrospun Polyelectrolyte Nanofibers
Hanzhao Duan, Xia Cheng, Lingping Zeng, Qiang Liao, Jianchuan Wang, Zidong Wei
Abstract
There has been a “trade-off” between ion exchange capacity (IEC) and mechanical properties in anion exchange membranes. Thinking out of the box, high ion conductivity was realized with only a small amount of ion exchange groups (means low IEC) in this work, by way of constructing highly effective ion channels with electrospun polyelectrolyte nanofibers. At a low IEC of 1.02 mmol g–1, the conductivity of quaternized poly(2,6-dimethyl-1,4-phenylene oxide) nanofiber (QPPONF)/poly(vinyl alcohol) (QPPONF/PVA) composite membranes achieved was 51.5 mS cm–1 at 60 °C, which was much higher than that of the homogenous QPPO casting membrane (20.3 mS cm–1 at 60 °C, IEC = 1.04 mmol g–1). Moreover, 70 wt % QPPONF/PVA composite membrane exhibits an excellent peak power density of 791 mW cm–2 in the H2/O2 fuel cell test.