Stable, Highly Conductive, Anion Exchange Polymer Films

A challenge in the development of anion exchange membranes for fuel cells is the design and synthesis of membranes that can endure highly alkaline environments while rapidly transporting hydroxides. A design for using cross-linked polymer membranes is disclosed to produce ionic highways along charge-delocalized pyrazoliums and homoconjugated triptycenes. Compared to existing materials, the ionic highway membrane systems have higher conductivities at reduced hydration and ionic exchange capacities. The membranes retain more than 75% of initial conductivity after 30 days of alkaline stability test. This effective water management through ionic highways is confirmed by density functional theory and Monte Carlo studies. A single cell with platinum group metal catalysts at 80 deg °C showed a high peak density of 0.73 W cm-2 and stable performance during 400 h tests.