Cross-linked anion exchange membranes with pendent quaternary pyrrolidonium salts for alkaline polymer electrolyte membrane fuel cells

• Novel anion exchange membranes based on pyrrolidonium salts and PVA were prepared.
• The properties of the membranes could be tuned by varying the blending ratios.
• The membranes showed excellent thermal, chemical and dimensional stability.
• The membranes displayed the high OH− conductivity of above 10−2 S cm−1 at 25 °C.
• A peek power density of 88.9 mW cm−2 of the H2/air fuel cell was obtained at 65 °C.

Novel anion-exchange membranes based on two kinds of pyrrolidonium type ionic liquids, N-methyl-N-vinyl-pyrrolidonium (NVMP) and N-ethyl-N-vinyl-pyrrolidonium (NVEP), have been synthesized via polymerization and crosslinking treatment, followed by membrane casting. The covalent cross-linked structures of these membranes are confirmed by FT-IR. The obtained membranes are also characterized in terms of water uptake, ion exchange capacity (IEC), ionic conductivity as well as thermal, dimensional and chemical stability. The membranes display hydroxide conductivity of above 10−2 S cm−1 at 25 °C. Excellent thermal stability with onset degradation temperature above 235 °C, good alkaline stability in 6 mol L−1 NaOH at 60 °C for 168 h and remarkable dimensional stability of the resulting membranes have been proved. H2/air single fuel cells employed membrane M3 and N3 show the open-circuit voltage (OCV) of 0.953 V and 0.933 V, and the maximum power density of 88.90 mW cm−2 and 81.90 mW cm−2 at the current density of 175 mA cm−2 and 200 mA cm−2 at 65 °C, respectively.